My wing man Red Baron introduced MLR to me by being direct with the girl you want to date multiple women. My wants differed that I don't want to spend time dating as much as having sex and using my constraints to my desires due to my career. I took my wing man's approach on being direct. I have ten qualities I seek a woman and I am direct when one does not meet it, but I state I am attracted to her in a way that leads to FWB scenario's with multiple women.
Just boils down to qualification, being direct and being open with what you want. Hope this helps you like it has me.