if you quick hits for your forum, my suggest is adwords but if you want hits from se for a long , i think you must apply seo for your forum
Before promoting a forum, make sure you have a decent amount of members, threads and post (even if you have to pay posters). People usually don't like to join forums that are empty.
Promoting a forum is different from promoting a site mainly because you need people to be stuck in your forums and be talking around, but websites dont need that.. As 8everything said, people wont like to join empty forums
Yes, the starting point is clear above - it's pointless to promote if you don't have any forum posts written. As soon as you have some posts to boast of, then you can bravely start your active forum promotion. Good luck there! --Tiggs
When I first started out, I made about 10 accounts and talked to myself. Takes a lot of time, but makes your forum look active.
It's different because people will not come back if nobody reply to their questions. This don't happen for a site or a blog.