The key ingredients in a good drop shot are shortness, softness, and backspin. Your goal is to get the ball to bounce twice before your opponent can get to it, so it's the shortness of the second bounce that matters most. Having a short first bounce is a good start, but you also need low ball speed and backspin to keep the second bounce as short as possible. The best drop shots actually bounce back toward the net, making the second bounce shorter than the first.
To create backspin, you must brush down the back of the ball with your strings. Anytime you brush down on the ball, you must also tilt your racquet face upward to compensate and give the ball some lift to go over the net.
For most players, the easiest grip for forehand drop shots is the Eastern forehand, but a Semi-Western grip can work (uncomfortably, given its reluctance to tilt upward), and a Continental grip naturally tilts upward, though often too much if you're not used to it. For backhand drop shots, a one-handed, Eastern (modified or full) or Continental grip is usually best. Many players tilt too much with the Continental and have more control with the Eastern. Only a very small minority of two-handed backhanders use two hands on the drop shot.
Start the swing with your racquet roughly a foot higher than and two feet farther back than your intended point of contact. Use a short, gentle motion, angling forward and downward. The amount of tilt in your racquet face must be adjusted for your swing path and speed, but you'll usually tilt back between 30 and 50 degrees. Create the downward motion primarily from your larger muscles, pivoting from the shoulder and elbow more than the wrist and bending your knees as you hit to accentuate the downward path.
The best way to develop a drop shot is to hit lots of them. Here's a progression that will make the practice fun:
- Get a friend or a pro to feed you balls with each of you at your respective service lines.
- Your goal should be to get the ball to pass no more than three feet above the net and bounce at least three times before passing the opposite service line. (A higher ball, no matter how short, would give your opponent too much time in a match situation.)
- Stay at your service line until you hit a drop shot that meets this test. Then, each time you hit a good dropper, take one medium step back. Keep going until you get back to 7/8 of the distance from the net to the baseline. (Trying drop shots from any farther back in a match usually doesn't pay off, because the farther your ball has to travel, the harder it is to hit short and the more time your opponent has to run forward.)