Optimize your Twitter bio.
Find out who the influencers and experts are in your target area(s) and interact with them on a regular basis.
Get colleagues involved.
Tweet regularly.
Don't be afraid to ask for some Twitter love.
Track mentions -- and respond if appropriate.
Retweet.
Favorite tweets.
Start marketing your book, and gain fans with a vested interest in seeing your book succeed. Set up a lead generating landing page, and ask your prospects to choose from 2 or 3 book covers. Use the cover that gets the most votes