Send some interesting tweets. You could also add some people, but make sure they are interested in what you have to say. Having tons of followers who are not interested in what you have to offer are useless.
Do a search for twitter tools, most of the sites with good twitter tools have a community where you can post a link to your twitter page, and even communicate gaining popularity. This could get you a few followers. Plus it adds to your conversation on your twitter account when you post that your using a new tool.
Getting people to follow you faster? Well, I get followed-back immediately (~some hours) if they auto-follow those that follow them!
Add a lot of people. Delete the ones that do not follow you. Target people you share things in common with. Be interesting. Post things often.(not really boring stuff like "I am driving now" or "I am at the store now")
Follow more and more people and they will follow you back, that is just a simple technique to get more and more followers.