How should I advertise a forum?

[Untouch]

I feel like any method of advertising I use other than using a forum signature is either annoying to others or doesn't work at all. Any ways to get members to join a forum (I do have some money for advertising set aside)?

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I know that because it is just a general forum, I'm already at a disadvantage, but I really think the current members make the forum different than most and the whole group wants to make the forum successful.

It's not all about advertising, if someone goes onto your site what is it that will appeal to them to make them register or come back?
It needs to look slick also try not to create sub forums which have no threads. You want to make your forum look as active as possible.
Also think about what the members will gain from going on.
Then start thinking about advertising.