Google ban adds..
* unless the forum is about something interesting that people have a need for, it won't really go anywhere. If you don't have a target audience, then it may well not go anywhere either.
*promote your forum to people that interested in the topic and the layout must simple not ennoying people.
*Find a decent host with good uptime, you can't become known, if no one can get to your site.
*Make posts yourself, if you make posts yourself, it will entice people to register and post, and they will start making new topics hopefully, and it will grow from there
*Find some link directories, submit your site.
*Put your sites URL in your signatures of all the forums you are registered in, maybe even FeedBurn your sites RSS feed and put it in your signature