'Positioning is important,' he emphasised.
Set up your feet behind the baseline with where you want the ball to go.
Your left foot should be in front at an angle. Your right foot should be behind, parallel to the baseline.
You should point your racket forward to the target. Your left hand, with ball in hand, should be placed at the neck of the racket.
The racket should be at about waist level.
Next is the tough part, which requires balance, rhythm and timing.
Move your hands down together. At the same time, you should transfer your weight to the back foot.
Then, bring both arms back up together, tossing the ball up simultaneously.
Your left arm should be straight and your right arm bent 90 degrees.
Bend your knees and bring your racket down behind your back in a throwing position.
Your racket swing should be timed to contact the ball as it reaches the top of the toss - about 15cm above your outstretched racket and slightly in front of you.
The higher you make contact, the more power you will be able to generate.
Snap your wrist, following through across your body.
For a simpler alternative, Dewandaka recommends the half swing instead of the full.
Start with your right arm up, bent at 90 degrees, then toss the ball and hit.
Even some professionals, like Andy Roddick, do the half-swing - and he holds the record for the world's fastest serve at 249.4 kmh.