Actually, these are controls for my keyboard, but could vary:
S: serving ; A:attack ; D:defense
L:
S: towering serve
A: spike
D: block
The button near L, to the right:
S: jump serve
ress first time to throw ball in air, second to jump&hit
A: set
D: set
The button further on the right:
S: normal serve
ress first time to throw ball in air, second to hit
A: bump
D: bump
You move with arrows or with keypad (the one to the right of keyboard, with 9 numbers)
That's all folks!