It about the Floater serve

 The Floater serve

The Floater is one of the two main overhand serves. You will begin by facing the net with your feet slightly apart, non_dominant foot forward. Most of your weight should be on your back foot. As you toss it straight up, don't launch it high

Floater serve

Begin with the ball in your non_dominant hand and a great tip is to start with the air hole of the ball in your palm. If you begin this way the ball is going to start with the heaviest part of the ball pointing down, which make it more likely to float or drift in the air. As you toss it straight up, don't launch it  hight into the air, you simply want to raise it quickly to the height. Your aim can extend for your overhand swing, so usually 12 to 18 inches above your tossing hands.

Floating serve 

Dig the ball

Toss the ball

You should be releasing the toss about level with your head. So the ball will be placed in front of your hitting shoulder and you will be stepping into it with your swing. Now step forward and swing with an open palm, finger spread, you want to slap the ball with your firm palm and pop it making contact right in the ball.