This is probably one of the greatest advices on making a forum site grow. Make no mistake about it. Follow this path of wisdom and your forum will become an empire in due time.
You can make fake accounts and post, or you can post interesting subjects yourself, but you MUST have some content on your forum in order to get members. I don't believe that anyone is going to register on an empty forum.
at the beginning it sould be lots of input to the forum by you it will be most you doing all of the posting and make sure you reply to every post and reply quite quickly so people are more likely to come back