I did was promote my SFI gateway on Facebook. Now SFI is blocked on Facebook, but there is a way you can post and not get blocked. It's free http://m.youtube.com/watch?feature=youtu.be&v=kDT7sNSrwD0
Also promoting on Twitter was quite helpful.
The last thing I did was order a Co-Op. If your on a limited income then I wouldn't suggest this. In my opinion, this is a great tool but it does not promise active members.
I hope this helps, much success headed your way!!!
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