19 Ways to get Followers on Twitter

1. Follow users with at least 5000 followers who have a balanced follower to following ratio
2. Add "I follow all followers" to your twitter profile
3. Set up multiple twitter accounts
4. Never spam peoples mentions/reply box
5. Don't unfollow someone you've followed if they've followed you back
6. Have interesting tweets
7. Follow all users that follow you
8. Have an interesting twitter profile that gets users to want to follow you
9. Tweet with #hash tags when appropriate
10. Have a good last tweet
11. Unfollow users who stop following you
12. Automate the process. I recommend Twixcel probably because I wrote it.
13. Follow all people that follow you
14. If some doesn't follow you back or unfollows you, don't follow them with your other twitter accounts
15. Participate in Trending topics
16. Follow users with automated tools over users who don't use tools
17. Tweet at least once a day
19. Subject tweet