What is a way to separate my guest from other @ a lrg club where my guest will get in free and others wont?

I am hosting a party @ a bar that charges a cover on saturday nites my guests will be allowed to get in free what can i do/provide to the bouncers so that they will know my guest and let them in at no charge i've already thought of wrist bans but that seems like too much work since i have people coming from all parts of chicago, please help