Tony Lee's Professional Tennis School

The flat serve is a very effective weapon, as it is the fastest serve.

Grip the racket with a Continental grip, not a forehand grip.
Stand near the centre mark for hitting down the centreline. Stand farther from the centre mark for a wide, flat serve.
Assume the normal posture for a serve, with a sideways stance and your hands down.
Throw the racket to the "back-scratch" position as you toss the ball in front of you.
Toss the ball farther in front than you would for a slice, topspin or kick serve and farther to your right for right-handed hitters.
Throw your racket out of the back-scratch position, with your palm facing the net at contact with the ball.
Hit the ball with your arm fully extended.
Let your arm finish the serve on either the right or left side of your body.

Mix a flat serve with other service choices, so it will not be predictable to your opponent.
Practice hitting down the line on the deuce side and serving wide on the ad side.

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