High Volley (top image):

If the opposing team gives you a volley above the waist, it’s time to go on offense. Either attack the opposing net player by hitting at his or her feet or angle the ball away for a winner.

Low Volley (bottom image):

If you have to hit a low volley, you must play defensively. Bend your knees and hit your volley deep and up the middle toward the baseline player (and keep it fairly low, so you don’t give the opposing net player an easy poach). The goal is to stay in the point and get a better look at a winning volley later. If both opponents are at the net, volley low and between them. The goal here is to force them to volley up or, even better, to confuse them about who should hit the volley.