Bunker shots require a high launch angle to get the ball up and over the bunker face. In order to achieve this high shot you would usually open your club face so that you have added loft on the club to play the shot with.
Entering the bunker and facing a buried lie would instinctively make you think that you would need to open the club face up. However, this is completely the incorrect approach. In order to play a great golf shot from a buried lie, you actually need to close the club face.
Set up as you usually would to play a golf shot with the club face aiming at the target. Play the ball slightly forward in your stance, just left of centre (for right handed golfers). Place more weight on your left side and close the club face, turn the handle to the left and then hold it. Work on hinging your wrist very quickly during your backswing to get height into the club head. Now as you swing down towards the ball, work on striking down on the sand aggressively, two inches before the ball and get the toe of the club to strike the sand first.
As the toe strikes the sand, the impact will slow this area of the club head down, however the heel will continue to travel at the higher speed and will accelerate past the toe, making a scooping or digging action into the sand, that will dig under the ball and force the ball out of the buried lie and out of the bunker.
Strike the toe of the club head down aggressively into the sand, two inches before the ball and allow the club head to do the work of digging the ball out of the sand.
Keep the club head moving through the sand and ensure that you turn your body through the shot towards the target as you finish the shot.
Using this technique will get you playing great golf shots from some very difficult, buried lies and will help you to lower your score when you are next out on the golf course.