Butterfly money muscle

Ive done the search and lots of good information. When you butterfly the money muscle, how big are you going? I notice the actual money muscle is pretty small, a lot of the pics and videos show a cut maybe 3 inches back from the front edge of the butt. When I cut there I'm getting at least two different muscles with a fat vein in between. Also there is a tendencie for the two to kinda sluff apart. So I'm wondering am I going to big? Do I need to pin those together with toothpicks? Help!