No single men allowed. (Unless you're holding a gangbang or a gay orgy.) Thirsty dudes will overwhelm your orgy. In general, you need to be a hetero couple, lesbian couple, or single woman to get into the swing scene. If you're a gay man, and you have trouble finding gay orgies, there is probably something socially or physically bad wrong with you.
It's a stereotype, but gay guys know how to party and don't fuck around about fucking around.
See if there is a local swingers group on FetLife.
The best orgies just kind of spontaneously happen. You usually have to have a close knit core of friends. After parties for kink events and such.
Sharing Ecstasy/MDMA with close friends can make one happen.
Orgies are too complicated. Too many people feel left out of the fun if they are not getting fucked. Spouse Swapping is easier with only 4 people needed to reach agreement on pre conditions.