For you to have more followers' on twitter, you must be a person of fun. You need to be updating people through you twitter on what happening in the world today. Twitters followers' needs to be updated on the real time based on what's happening in the world of celebrities', education, important events, and movies.
Depends entirely on what kind of followers you want. To just get a lot of followers and you don't care if they aren't even people, just goto fiverr.com and pay someone 5 bucks to follow you. Or just mass follow a lot of people and hope for follow backs.