Sorry for not replying earlier, I just kind of got side tracked ><
1) get more people to sign up
- Give them a reason. Looking at it I wouldn't join, because I can find loads of other boards offering similar areas of discussion. You have alot of forums, compact some down together. While you don't have a small post count, they are spread out giving the illusion the forum isn't as busy.
2) get the people I have to be active
- Offer some unique angle of discussion. Give them a reason to contribute. Maybe offer different levels of membership. For example a group for people getting over x posts of something. For your genre you could hold contest that relate to certain parts of the board (graphics/writing/poetry), then give the winner recognition.
3) Keep all these new members I should be getting to stay and stay active
- This is similar to question 2... So read my reply for that one
The answers are kind of similar, just thoughts =) They aren't guaranteed to work
Please igonre the typo's, I am a sloppy typist xD