If you want to hit better bunker shots (who doesn't?), you have to eschew conventional swing wisdom and do things a little differently. For instance, in a normal swing, usually you shift weight away from the target going back, then toward the target on the downswing. With greenside bunkers, I encourage my students to do neither! If anything, the best advice I can give you for more sand success is to remember to favor your left side through the stroke.
Staying "left" means setting up with some forward shaft lean, your weight mostly over your left leg and through the stroke, keeping it there well into the finish.
What this does is steepen your angle of attack and help you better use the sand to lift the ball, not the clubhead. Just remember, when you do this, you have to be aggressive with the hands and accelerate through the sand as best you can. Allow the body to rotate as it normally does and the hands to release, again, as they normally would. You can see in this sequence of photos that I keep my weight mostly over my left leg through the entire stroke. If you haven't tried this, it may feel strange at first, but you'll quickly see how much more effective it can be. Also, notice how I made a divot under the ball, not behind it. Staying left will help prevent you from hitting too far behind the ball into the sand.
When you hang back on your right side and try and lift the ball out, you'll run into trouble. But if you stay left, you'll steepen your attack and have a better chance of extracting the ball from the sand. Remember, left is right for better bunker shots!
Pomp Braswell is the director of instruction at the Jim McLean Golf School at SunRidge Canyon in Fountain Hills, Arizona. Visit sunridgegolf.com.Hitting successful bunker shots means not shifting your weight too much! Get left, hit left, finish left!