Aw, this is a nice post. I know I appreciate respectful teammates and it's nice to see that you put in an effort to make a girl feel welcome. Just don't overthink it! I've been in groups of awful, sexual, thick headed hooligans, and in a group of all cops that couldn't swear in front of me and kept saying "oh darn" when they died instead of the curse word they were (obviously) thinking of. So I've seen the whole range of teammates. And honestly the most fun ones are the ones that didn't even acknowledge I was a girl. They just went about their business and made the same jokes they normally would and were in general just nice to talk to. If you must get flustered, definitely aim for the more respectful end of the spectrum, but really just relax and have fun. :) don't worry about creating a different atmosphere, I like gaming with men because I love listening to all the joking around and making fun of each other that you do. It's hilarious! And it's fun to pretend I'm one of the boys ;)