Tony Lee's Professional Tennis School

Service Action A slice serve is usually the first serve learned by tennis players

Hold the racket in a continental grip
Stand anywhere from the center mark to about 6 or 8 feet from it.
Assume the regular serve posture, standing sideways to the net. If you were to draw a line across your toe tips and extend it, it would indicate the direction of the ball.
Keep your arms down and relaxed to begin with.
Hold the racket at the throat with the nonhitting hand. Your hitting hand should be as loose as possible on the grip.
Shift about 80 percent of your body weight to the back leg to start.
Shift your weight forward simultaneously with your hands as they go up.
Toss the ball and throw the racket to the back-scratch position.
Dip your hip in toward the net as the upper body rotates.
Throw the racket head aggressively up and over your shoulder, hitting the ball out and in front of you, to the right.
Transfer your body weight, uncoiling your upper body, and thrust upward from the legs as you hit the ball.
Fold in your tossing arm (which is your brake arm) quickly toward the chest as you make contact with the ball; this stops the shoulder rotation. The weight transfer carries the body forward onto the court.
Allow your feet to come off the ground or nearly off the ground.

Make sure to keep the tossing arm extended during the toss.
Practice this serve as a first or second serve.
Keep in mind that swing speed should be as fast with this serve as with a flat serve.

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