If you know of a few forums you could partner up with, you could do a link swap. Keep in mind, content is generally what will bring members to your community. If you do not have a great deal of posts or have a great deal of inactivity across your forum, you could hire a posting business to come in a drop a few posts.
The services do cost, though it's quick content. It's not always quality, though when you're paying .10-.15 per post, you can't expect the world

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