Hi

I can recommend the following :

- if you go to conferences, publish blog posts or keynotes, or comment online, make sure to add your twitter handle
- add your twitter handle in your email signature and business cards
- make sure your description is good. You can say : "I answer topics about management, journalism, and public relations in... every friday 2 to 4pm"
- i also find that my followers number (> 4000 currently) increases dramatically when I go to events or conferences. So make sure you advertise your twitter there. Use hashtags, live tweet the content of the event, comment on those who tweet as well.

Happy tweeting !