1. Treat your twitter profile as you would treat any other website. Send as much traffic as possible to your twitter profile.
2. Maintain good tweets in the first page of your profile. This seem to be a lot of work in the beginning. But seriously this will help you a lot in gaining followers. If people visiting your profile see only handful of links being tweeted, then they may not follow you, thinking that you are some sort of a automated script or some may think you as spammer. So see to that each time you decide to stop tweeting, make sure to tweet some useful things and minimize links. Because your recent tweets will be displayed in the first page of your profile.
3. Use a “tweet this” button below all your articles or below the articles which you think can go viral in twitter world.
4. Use different other services to know who is following you, and use the suggestion tool to get the suggested twitter users to follow. By this you can connect to relevant people around the world and they are most likely to follow you back, if they find you as relevant.
5. You can conduct twitter contests on your blog. This one strategy will drive a lot of followers in small amount of time. But it highly depends on what you are giving away in the contest. The higher the value of the product/service, higher the chances of getting more followers.
6. Get your twitter profile link featured on any famous website.
Ex:- If you are listed in the top 10 re-tweeters, then you can get still more followers. As people will think that you will re-tweet even their tweets!
7. If you have a website or a blog, display the follow me button at the top or any other highly visible regions.
If you get sudden hike in the traffic, you can’t expect that all those visitors will turn into your blogs subscribers or your loyal readers. But if they like the content of the blog they are most likely to follow you on twitter, as they think that you have the capacity to deliver the value.
8. Participate in twitter contests. By this you will be in a group of people who are into the contest, by this people participating may be willing to follow all other participants. So it is important that you leave a status message of the tweet or the twitter ID that you used to enter the contest, in the comment section, so that other participants can find you on twitter.
9. You can also use your twitter profile URL, while commenting on other blogs.
10. Participate in twitter actively. Re-tweet others useful tweets and get their attention. If they also re-tweet one of your tweets sometime, you will end up getting noticed by their followers, some of them may even follow you.
11. Use twitter ID in your email signature, so that your business partners or others will get to know that you are also using twitter.
12. Print the twitter profile URL on your business card.
13. If you have any other product, then you can get your twitter link printed on it.
14. Use your twitter URL at the end of each SMS(Short Messaging Service) from your phone.
15. Basic thing, but still ignored one: Invite all your friends in your Gmail, Yahoo mail etc, and they are the most potential followers you can ever get.
16. Tweet valuable things. Don’t just try to get traffic to your blog by tweeting only about your articles. You can tweet about what you are presently doing etc, bit personal things, this is what twitter followers like to know. But try to provide some more valuable things. Like tweeting a breaking news, cricket scores, latest happenings at your place etc.
17. Participate in certain groups. Groups can be created using hashtags. And some times if the group message is a hot topic, then your tweets will be listed in “hot trending topics” in search or other famous twitter services.
Ex:- #followfriday
18. Use a custom background for your twitter profile. This will show that you are a professional and chances are there, a visitor to your profile may turn into your follower.
19. Use a good twitter ID. Many people suggest to use their real name and most of the others suggest to use the business name. In case of bloggers, people mostly use their blog name inorder to build their brand recognition. If the twitter ID is somethink special or attractive, many people will endup following you without any reason!
And many such attractive twitter ID’s are auctioned at different marketplaces. It shows the importance of having a good twitter ID. And make sure that your twitter ID is not too long, which will eventually add up to the 140 character of the person who is tweeting you or re-tweeting your tweets!
20. Try to involve in conversation with people having more number of followers. When the famous person reply to your tweet, his followers see your twitter ID, if they find the conversation interesting, they may start following you and the conversation.
21. Use your twitter URL in other social networking, social bookmarking and social media sites profile page and any other online places where you have an account and space to write something. This will help you get interesting and targeted people follow you.
22. Do not use annoying profile picture. Using your real photo or your blog logo/banner is recommended. Many people use the animated images, this is ok as long as its not annoying.
23. Link to your twitter profile often. You can also add a link to your profile at the end of each article on your blog.
24. If you have an online service, then use Twitter as another tool for tech/customer support. This will make the customers to follow you inevitably!
25. Include your twitter ID in forum signature.
26. You can ask other twitterers to recommend you to their followers and you can recommend them to your followers.
27. Some bloggers publish the twitter IDs of some people as: Recommended to follow list. You can participate in such events and if your ID has been listed, you can get a lot of followers.
28. Some bloggers also collect the twitter IDs of their readers and publish on their blog, for mass following. Participate in such events and you will keep getting a lot of followers from that single page over years.
29. Some people mass follow others as they are sure that most of them followback almost all their followers. Once they reach a certain target number, they will start un-following those mass followed people. Thus they will be able to have a high number of followers with a low number of following! This is not a recommended strategy, but its still popular and most effective.
30. Utilize the about me section of twitter properly. Put your blog URL or about your business along with your small description. If you make it interesting, there is a high possibility of getting more conversions(visitors into followers). Remember, your bio is shown in the Suggested Users section, that will highly decide your number!
31. Follow others. If you do not follow anyone and keep expecting lot of people to start following you, this will not work for everyone. If you are following atleast some people, then others will feel that you are open to conversation and that you like to listen to others.
32. Remember you only have 5 to 7 seconds to convert a visitor into follower, so make your profile as good as possible. Tweak all the aspects mentioned above(related to profile page), and you can see a drastic increase in your followers number.
33. Try to pay individual attention as for as possible. Don’t just think of yourself! You can talk to one person at a time. But never isolate yourself after having all these followers. People may find you inactive and may start removing you from their following list.
34. Be helpful to other twitter users, so that they can recommend you to others, without your request.
35. Block spammers and other useless automated boots by using the blocking feature in twitter. By this you will be able to give your attention to only genuine users and will not get distracted and your twitter experience will be good. By this you can give more to twitter and get more followers.
36. If you have some 500+ followers, you can use some service to display it on your blog, as a social proof. This will defiantly attract more people to follow you. Inturn increasing your followers number and inturn attracting even more people to follow you.
37. Ask questions: By asking questions, you can easily start the conversation with any stranger. Make sure that you ask an easy question 
38. Use some twitter client or twitter apps or twitter messengers! Because people don’t like to wait for your reply. If you are still using the web page(with no AJAX implemented), then its time to switch to some twitter client and start replying. This saves a lot of time and followers! If you reply to your followers question after 24hrs or even 2 or 4 hrs late, then they probably don’t enjoy your conversation. And eventually may stop following you.
39. Tweeting at the time of US business hours i.e., from morning 9:00 to 5:00 evening would help to grow the twitter followers. I have not tested it extensively though, but still it sounds logical.
40. This tip for people who need to get followers at any cost:
You can use the PPC advertising to get the targeted twitter followers. This may seem very crazy in the beginning. But wait, this idea is better than paying twitter or any other service to feature your twitter ID.
This idea is for people who are running any business and want to get some target audience to follow them, so that they can serve those target audience.
41. If asking question is one strategy to build the followers, answering others question is another way to grab the attention. If you are following a famous person and if he is not following you, then its the right time to start replying/answering to all of his questions, as aptly as possible. By this way you can get his attention. And you can also get his followers attention, if you can make him to reply to you quite often.
42. Similar to the importance of tweeting time, the days that you spend on twitter also matters. On Saturdays and Sundays there will be less people using twitter. As people are free on these days, you may be thinking that they will spend a lot of time in these social sites, but it doesn’t work like that. People want to enjoy their life. They want to spend their valuable time with their family. So most of them or atleast those with success in their business will turn off their internet on these days.
So it will be of more beneficial, if we can follow all the strategies to get more followers, on days other than Saturday’s and Sunday’s.
43. Many of you may not think this as an ideal way to tweet, but this tip has proved to be most effective.
People follow a blog that they are interested in. The more focused a blog is upon a particular niche, more chances of it getting loyal reader base. Similarly, I have seen many people tweeting only about a particular topic, say politics, health and fitness, Google news, gadgets etc, get more number of target followers.
This also helps to get more re-tweets and drives more traffic to a blog post. For example, if you have a popular or even not so popular gadget blog, and if you tweet mostly about interesting and latest gadgets then gadget lovers will surly like, follow and recommend you to their followers.
44. If you are a blogger, then try to follow more people in your niche. Because these people are more likely to follow you back because of the niche that you are in. To help them get to know about your niche and interests, use the about me section effectively.
45. If you can use the twitter SMS feature or if you have internet in your mobile phone, then cover some live events.
Ex:- If you are attending a famous conference/sports…etc and if you can tweet about the happenings live, then more people tend to follow you and re-tweet your tweets. Use hashtags and people will notice you while they are searching for the news of that particular event that you are live tweeting.
46. Using twitter clients can make things easy and fast. But make sure that you do not tweet every second of your online time. This will surly annoy your followers and even twitter!
People will consider you as a spammer or an automated script, if you keep on tweeting, without listening and responding your followers tweets. Minimize your personal tweets. Try to involve in the conversation going on. Provide value.
47. If possible, teach your followers what re-tweeting is. By this, if your followers start re-tweeting your tweets, then your ID will again appear infront of your followers followers, and you will get more exposure and high chances of getting even more followers and even more re-tweets.
48. If you have a podcast service or if you shot a video and upload it to YouTube, then make sure to add your twitter ID in the video/podcast, at the end or in the beginning of the video/podcast. If people like the video/podcast, then they will surly like to get connected with you and start following you on twitter.
49. Follow the top twitter users and watch what they tweet and how they treat their followers. This may not be a huge tip, because those top twitter users are already popular in other fields, so they have lot of followers in twitter. While this is true in most of the cases, but there are some twitter users who have got a lot of followers just due to their tweets. Follow such people and you will learn a lot from them.
Being a celebrity doesn’t hurt.. but just being yourself brings followers that actually care about what you are saying and they are much more valuable.
50. Have your twitter ID on all the guest posts that you write.
51. An effective and worst way to increase your follower base (spammers way to get more followers) is to create an account with a celebrity name and profile pic, and try to pretend like the celebrity. In a very short time, you will get a lot of followers. After you are satisfied with the number of followers, change the profile pic, bio and the twitter ID and behave normally.
This is not a recommended thing to do. But I am writing this article to those people who want to know almost all the possible ways to increase their followers.
Personally I don’t find any useful thing (other than getting traffic) in getting more followers. And I am not interested in the number, but in the person that I follow, because we get, from whom we follow. Whom others follow is left to them.
52. Biggest tip to enjoy twitter is, to tweet just for the sake of tweet. Don’t think of the number of followers. Just try to get involved in the conversation. Have interest to know about other people around the world. Be curious, enthusiastic. And spend some time using twitter each day(if you have time), and eventually you will have a lot of followers who are also interested in you.
53. Following everyone who follows you is also a best way to get more followers. People will follow you atleast because you asure them that you also follow them back.
54. When you tweet something worth Re-tweeting, then use less than 140 Characters. Because, if your twitter ID has 5 characters, then a re-tweet will add a @ symbol and “RT:” thus making a total of 140+1+3+5=149 characters. So use 125 or 130 characters. Tweets which involve breaking news or some offers/discount coupons or anything that you think might go viral in twitter.
55. Tweeting link of some good pictures and breaking news get viral most of the times. You can also tweet about a new job or event.
56. Offer some free stuffs for following you. I have seen some people doing this, and not surprisingly, they have a lot of followers. But once you get people following you, its all about providing value and retaining them as your followers.
57. Write an ebook(of good quality) about Twitter and start distributing it for FREE. You can even upload it to torrent sites etc. If you can make that ebook go viral, then you will surly get a lot of followers, as people who download and read it must be interested in Twitter and if they find the ebook of any use, they will start following you.
58. In the “about me” section of Twitter, there is a place where you can display your website URL. There, you can use a good quality article(better, if you have a good article related to Twitter) link instead of just linking your blogs homepage. By this way, people who check your website before following you, may get interest in you, if they like that article.
59. Write some interesting articles about Twitter on your blog, so that, people searching for Twitter related things find it useful and start following you, expecting more such valuable contents and tweets from you.
60. You can also list your Twitter ID on some Twitter directory services. Make sure that you opt into proper category. Such services will allow you to choose some topics of your interest and place you in those categories and it will show your ID to those who have similar interests to that of yours. So you will get targeted followers.
61. You can also use some services that asure you to increase your twitter followers, by listing your Twitter profile link on their site. Also take care that you do not give your twitter ID along with your passwords to such services. Use only genuine services. Ask people who have already used the service.
62. Try to help people as much as possible. This way, people will surely point some one with similar problem to you and high chances that they will start following you.
63. Run a poll: This actually works if you have high number of followers. But you can make it work the other way too.
Make the poll interesting. And request people to re-tweet about the poll.
64. Use Cross promotion techniques: Explicitly(while chatting in any messengers, talking in phone etc – Out side twitter ) ask a Twitterer to mention about your ID to his followers and in return you do the same for them.
Source:technotip.org
The biggest problem that occurs when increasing your followers/following count is managing those connections. It becomes harder to keep track of why you followed someone or why someone may have followed you. As the list increases it also becomes harder to follow your “real” connections & those that are just information firehoses. If you happen to be experiencing this problem now, check out 
AHH, the noise! Twitter can become a horrible place when off-topic noise suddenly floods your Twitter stream. People are forever changing their minds or expanding their interests. In doing so, those new followers may have absolutely nothing in common with what you relate to on Twitter or current followers may become irrelevant to you. Do you really want to constantly prune through thousands of followers just to continuously get a better signal-to-noise ratio?
In turn, taking part in these off-topic conversations can change the flow, context, and content of your own Twitter stream. With an increase of followers comes the task of staying on topic and not abandoning your “original” audience, which I like to think of as the first 400 people to follow you.
