Mike Malaska shows several ways that you can control distance.
First, you can control it by the length of the swing. Second, you can control it with the amount of sand you take, and three, you can control distance with the club.
Mike illustrates hitting out of the bunker with different lengths of his swing to get the ball closer to the pin.
When controlling the amount of sand you take, you don't want to take a small amount of sand when you swing. Most people aren't good enough or haven't spent much time practicing in the bunkers to be good at that. Your goal is to get the ball out of the bunker and somewhere on the green.
People tend to get nervous when they must hit close to the ball. Try to control your speed mainly with the length of the club swing and maybe a little by controlling the sand.
Another way is the choice of club. Go from a 60-degree sand wedge to a pitching wedge. The club will carry the ball an extra 5 to 10 yards farther with the same swing. When you change clubs, there is less loft, and the club will throw the sand and the ball out farther.
Practicing with different clubs and ways to control distance is a good idea. You will start to calibrate your distance with these other options.
Again, length is controlled by the length of the swing, which is the speed of the club, how much sand you take, or the angle of the face.