Well, the first you could do is start up a few interesting threads. This way the board won't look death. And people can see when you posted them, if they see, 'owh, that guy posted this today,' the board will look allot better then if it's completly empty. Give guests something to view, and new members something to reply/discuss in.
Second, try to advertise your board on other boards with the same or partly the same theme. Maybe it's also an idea to affiliate with them, so you'll get more traffic to your board. I don't know what kind off board you have, but you could always try to advertise on InvisionFree Skin Zone. Mostly, this could get you a few members. It's always worth the try.
Just try advertise for the coming weeks, and ask your members to do that as well. Make some nice graphics they could use in their signatures etc.
Good luck, I hope this helped you a bit

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