Hitting from Soft Bunker (Sand)
If the bunker has soft sand, the clubhead tends to dig too much into the sand causing you to leave the shot short.
To prevent the clubhead to dig too much into the sand, you need to take advantage of the bounce that is designed on the sole of your clubhead.
The bounce on the sole will prevent the clubhead to dig too much into the sand.
To use your bounce correctly, you need to open the face of your sand wedge first before gripping the club. Open the face and then grip it.
This will help clubhead to slide through the sand.
Just remember that if you open your face more, the ball will go higher and fly shorter. So you need to swing harder to compensate.
The Angle of Approach into the sand
For bunker shots, the clubhead enters into the sand and then slide under the ball.
To hit consistent bunker shots, you want to pay attention to the incidence angle of clubhead as it enters the sand.
You don't want to hit down into the sand. You want the clubhead to enter the sand with a slight descending angle.
So you want to take a shallow divot in the sand.