Recurring comission for affiliates

Sorry for posting same question again. I'm a bit in a hurry trying to solve this by myself so I don't have to hire another programer.

So I want to enable recurring comission for all affiliates who bring new premium members to our site and I'm not sure that I know the right way to acomplish this.

If you can help then please provide detailed explanation on how to achieve this. I would like to know where to put code needed for this to work, and also, how does that code look like. If you can't help then please don't bother to answer this post.

Thanks in advance!