I've been wondering about this for a long time now. My forum (discusstheweb.net) is a very new forum in the world, and I've always wondered how extremely new forums rise up so fast? I know many ways which people would tell me to do such as create interesting discussions, buy forum posts, buy ad space, make forum competitions - but that doesn't seem to be working - at all. I guess the forum structure must be interesting, and there should be many posts also. What do you think of this?
Discuss it with friends, have as least forums as you can. That way it looks more active with less posts, and just have referrals. Maybe giveaway's, and competitions to the person with the most referrals.
Why should a random visitor register and contribute? I would choose a unique niche that you know very well (white fluffy bunnies with red eyes) and which nobody else is focused on. If somebody googles the white fluffy bunny and finds your forum, they'll be more likely to post on your forum than on one focused on everything (where are usually no experts).