- Find the big players on Twitter and follow them.
- Send a message to these big players. Perception is sometimes reality. In that it may look like you know these big players. People see that and will start to follow you.
- Provide a professional looking avatar, but one that stands out. Upload a larger version (around 500x500 px) for best effect.
- Follow everyone that follows you. (Not a fan of this school of thought)
- Link to interesting stories, just don't keep writing about your cat.
- Repeat your tweets. (I would say at a maximum twice...otherwise looks desperate and spammy if any more)
- Ask people to follow you
I encourage you to read the entire post as well as the 100+ comments for some additional insight to increase your followers. Good luck!