Consistency is your ultimate weapon!
Get to the kitchen or non-volley zone(NVZ) at first chance.
Check the pressure in your grip. Novices tend to tighten their grip. Staying relaxed and calm will help your grip pressure and your confidence.
Simplify your shot selection, follow through and don't be "wristy". A pronounced movement of the wrist leads to inconsistency.
Always strive to strike the ball when it is in front of you.
Volley if possible instead of stepping back and letting the ball bounce. You'll put more pressure on you opponent when you volley the ball.
Clear the net with room to spare.
Make sure your shot bounces in front of your opponent.