Joint Venture - Triangulation

I've been reading some reports on joint ventures and brokering deals. I'm interested in becoming a middleman and setting up two parties that could benefit from their relationship.

Say I know a cosmetic surgeon who did Botox injections and a hair salon owner. They could both benefit from sending clients to each other, on an onging basis.

How would you go about setting up the relationship? What would be some examples of how one would get paid for brokering the deal?

Thanks!