If you really want to be able to hit a great bunker shot with nice loft and spin, pay attention to your set up and posture. Many times golfers think in order to get the ball up quickly they have to have a steep decent in the sand behind the ball.
With this in mind we often set up with our hands too far forward and our weight too far on the back foot. This posture more often than not leads to the club to digging too deep into the sand bring up too much sand not spinning the ball, leaving the ball either in the bunker or just barely getting the ball out. The photo below on the left is an example of poor bunker set-up.
I like to set my hands back almost even or behind the ball. You may have to weaken your left hand for the grip to feel comfortable and to keep the club face square. Keep your upper body positioned forward (not tilting back) and to the ball, which is near your forward foot. The proper set-up for bunkers is pictured below to the right.
This ball position, grip and upper body posture promotes an easy hinge in your hands that gets the club up fast with out allowing the club to dig too deeply in the sand at impact. Always swing through to finish your swing to create a nice exploding bunker shot.