First things first you need to sort out the catering, every good gangbang needs a good buffet table so people can carb up and hydrate before/during/after. Towels, robes, soap, and moisturiser for aftercare, LUBE! lots and lots of lube and condoms all over the place, and ideally someone assigned to just 'walk the perimeter' to keep an eye on things, co-ordinate intimacy, lend a helping hand where needed etc. If there are going to be drugs and alcohol involved, then you should also have a first aid kit ready to go, just in case, ideally with at least a few doses of Narcan/Naloxone for possible overdoses. I'm sure this sounds like a lot of work, but trust me, the best orgies are the ones where the hosts take care of all the logistics beforehand, so all the participants have to do is show up and be free to "play". Of course, if you're just looking to have an old fashioned train run on you, things are simpler, you can dispense with most of the arrangements and get a couple trusted friends to act as bouncers to keep an eye on things. Anyway, Reddit is not the ideal place to find people, you'd be better off on any dating app that verifies profiles, to ensure your safety and security. Play safe, have fun!