1. No Inappropriate Stuff
This includes gore, nudity, sexual themes, profound language, etc. None of That.
2. Keep it Open
Don't get upset if someone posts a comment on your story. Even if you aren't done writing it, keep in mind that this is a forum and people are going to talk.
3. Don't Hound People
If someone doesn't post a new chapter/update for awhile, don't get on their case and pester them about it. They will get to it when they can and if they don't then that's their choice.
Well, that's it. Just follow the rules and have fun!