I place the grip of my bow directly below my thumb on the meaty part of the pad, w/ my knuckles at a 45 degree angle and my fingers relaxed. Not open, not closed, just resting there relaxed halfway between. I wish I had video online of my whole bow hand specifically, but this one will give you a good idea.

http://smg.photobucket.com/albums/v283/ringostar40/?action=view¤t=MOV00959.flv