If a golfer is unlucky enough to fall within the sand hazard, they must hit without knowing where to place the ball. A walk to the top of the hill will often be enough to site the flag on the green, but they must choose a tree or other feature of the course to act as the target. This sand hazard is deep enough that club with more loft is needed. The penalty for the golfer that finds their ball is this hazard is that the loft needed may make it impossible to reach the green on the next shot, so their penalty is extra shots.
Phil Mickelson's book "Secrets of the Short Game" on how to get out of a golf bunker or sand hazard made the most sense to me when I read about how to do it. His video below offers some helpful tips: