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Here is how you can use your throw to help you direct your serve more accurately.
As a general rule when I serve form this side, being a right hander I throw the ball out somewhere over the short line. Hopefully that gives me a good angle to hit the side wall.
If I am having a bad day though and I'm not hitting the side wall, the ball is being volleyed before it gets there, one thing I can do is just throw the ball slightly further back. Now when I strike the ball it is going to take it further to the right on the front wall and I'll hit the side wall earlier, hopefully preventing my opponent from volleying it.
Equally if I'm pushing my serve into the side wall too much I can tweak my throw slightly further forward, now I'm going to hit the front wall slightly further on the left, the ball will hit the side wall slightly further back and it will be difficult to get.
So it works this side too. If I throw the ball slightly further forward I'm going to hit the front wall slightly further to the left which will hit the side wall earlier. Of if I throw the ball slightly further back it will hit slightly further to the right on the front wall and it is going to hit the side wall a bit further back.
So just be tweaking your throw you can help direct where your serves are going. It is a lot easier than trying to do something clever with your wrist.