The way that matching works is that if you are shafted in an exchange, an effort will be made to match you to someone who has previously completed exchanges in the next exchange that you participate in. That works really well most of the time. You do not need to do anything additional on your end to receive the priority matching. Anyone who doesn't send a gift or who cannot provide proof that they shipped a gift is banned from all future exchanges. And if a rematcher doesn't follow through, they are banned from rematching as both a giver and a receiver.