Hello from the South Bay! My advice, like everyone else's, is to take things slowly and talk things out beforehand. I started in the lifestyle with my wife at the time, then as a single man, and now with a gf - so I feel as though I've been a newbie 3 different times, and each time has been wildly different. For me the best way to avoid jealousy has been the conversations we've had long before deciding to do anything. Talking things out, exploring fantasies without anyone else in the room, figuring out what's of interest, what's not, what's crossing the line - builds a trust between you that enhances your relationship. The more you talk, the more you find out about your partner and the tighter your bond is, to the point that when you do eventually put your hat in the ring, jealousy is the last thing on your mind.