...Topspin

...I sorry Lawrence. I really mean I added topspin in my last message but accidentally typed "Backspin"(I was thinking of something else at the time). The one where I hit the bottom part of the ball and pull my foot up as high as possible, to increase the spin. I even tried jumping up with the ball. I can't add enough topspin to the ball. Are there any more things I could do to add more topspin?