The volley is a stroke that you hit at the net before the ball hits the ground. The key to a good volley is to line the racket up, in front of you, with the incoming ball. If you did not move the ball would hit your racket and it will fall to the ground with not much power. However, if you step toward ball an instant before it contacts the racket, it will shoot off the racket like a rocket. If you also go up on your toes right before and drop to a flat-footed position right before the ball impacts the racket, then the ball will shoot off the racket like a turbo racket. This on the toes thing is good for giving a knack for what the feeling should be. You are learning to hit the ball with your feet not your arm!
Now you can add under spin or slice. Let start with your racket straight up down. First tilt it, with the head going away from you, 45 degrees; second, tilt the racket sideways 45 degrees so it looks like the incline of a hill; and, lastly, tilt racket back 45 degrees so the racket head is now also pointed behind you( and not just away from you). These angles will impart under spin on the ball so that you can control the hit better and increase the speed/penetration of the hit. Very little arm and hand movement are needed. No more than a tap from your hand is required.
Look up forehand and backhand volley positions on other sites so you can have a visual of what they look like.
The most important thing is W.I.L. (Watch It Leave). Don't look up until you watch the ball leave the racket. It is a scary feeling, but you will have enough time to react to your opponents return of volley. Plus you can really zone in on where you want to hit it for the next volley with little worry about a mishit.
