Okay here is what I have learned that has helped me beat my instructor in contests out of the bunker. 1). bend knees slightly 2). push right bent knee towards left knee (will help you not chunk ball or get to much sand) 3). open clubface slightly 4). make a bigger swing to get to a pin that is further away
Good Drill: 1). set ball in sand 2). draw a circle around the ball leaving an inch of space around the ball 3). hit on the edge of circle behind the ball 4). this will help you learn how much sand to take
Sand is easy if you have confidence. Most people panic when they don't need to. There some good answers like the girl that said draw a circle around the ball. That is a classic drill.
The key is hit behind the ball with a firm downswing and let the ball ride a wave of sand out. You can try the "open the face, aim ten feel left of the pin" technic, but I don't get the accuracy I want by doing that. If you are in a shallow bunker, try a half swing, punch and run. I actually works well and gives you a nice accurate shot.