On paper, throwing your ball up and smacking it perfectly in the middle of the racket looks easy, but it takes practice.
You can practice your form simply by performing ten swings in a row without a tennis ball.
Yes, without a tennis ball. On the eleventh swing, that’s when you’ll put the ball into the mix and see how you do.
You can also forget the hitting part and just toss the ball for a particular kind of serve (flat, slice, kick) and see where it bounces. If it bounces in the same spot repeatedly, you’re gaining consistency.
If it lands in the same spot repeatedly but that isn’t where it needs to be, you have something else to work on.
Consistency of toss is great, but not if it isn’t going where you want it to be.
Be open to working on your toss as much as you practice hitting serves.
The toss starts the whole thing off, so if it’s incorrect and you hit it anyway, the chances of a fault are pretty high.