Wear easy access clothing, maybe a skirt and a button down blouse, no bra and once everyone has had an adult beverage or two to relax make sure a couple of buttons are undone. Go sit next to the other husband, turn towards him, lean forward a little, look him in the eye with a sexy smile and whisper, "this isn't going to unbeaten itself big guy". If that doesn't get the party started, there won't BE a party!