I’ve been a few times over about 15 years or so. This was out in the woods, using gas-powered guns.
They’ve always been free sessions and they generally just allocate people on teams randomly, so there’s no promise the people you go with will be on the same team or not.
It really is just luck of the draw for the most part. Some people get stuck in, others don’t.
Don’t bother wearing loads of layers - it won’t make a difference when you get hit. You’ll be better off making sure you’re comfortable.
Plus, your mask is going to fog up, so the cooler you can stay, the less trouble you’ll have with it.
No idea of that helps, but take it for what you will!