You can promote true blogs (you can find a tutorial for this in the blog section).
The hard ways (but the most rewarding ones) would be to make an e book out of this (how to make an e-book can be found in the e-book section) where you tell them to use this because it is free and all the other reasons that I had already posted. Also tell them to use the referral method to get points or money . Use the forum links and nice graphic`s or if you have enough patience. you can even make a video about how to register, use it or get ref`s and also how to sell the gifts. Embed it there, it will look very good and convincing. After you have finished this e-book name it something like “how to make money without changing you lifestyle” or something convinceig and new( you figure it out). What to do nest is posted in the ebook section. You can also write about it on different forums or make some websites and post their banner there. There are a lot o free ways to advertise on the net you only have to find the strenght to go and search for them.