A greenside bunker shot is the only shot in golf where you are not hitting the golf ball. The club enters the sand before the ball and flies out of the bunker on a cushion of sand. In essence you are simply hitting behind the ball and fatting the shot.
The secret to making this happen is in the set-up and swing dynamic. In the set-up, play the ball forward of center, dig the feet in, but do not choke down. This combination insures that your club will hit the sand before the ball. Your swing dynamic is another huge factor in successfully executing greenside bunker shots.
Typically, golfers focus 2 to 3 inches behind the ball and find they have a difficult time hitting there and then following through. Focusing behind the ball can destroy good swing dynamics and usually leads to poor contact. Instead the golfer's focus should be on swinging through the ball, much like a pitch shot, relying on the set-up to produce the proper contact with the sand. This is how you make greenside bunker shots simple and easy.