Sometimes, you may be having problem with believing that hitting down on the middle of the ball can make it jump up. Or perhaps you do not really understand how that is possible.
Actually, when you jump a ball, you are trying to make the cue bounce off the cue ball as quickly as possible while driving the cue ball into the bed of the table. You need to let the cue get out of the way so the ball can jump. The action has to be very easy and loose because if you hold the cue too tight, the cue cannot get out of the way soon enough and you will trap the cue ball.
I usually recommend my customers to jump a chalk first. You still need to have the porper technique, like using a loose grip, and try to keep your elbow up and to hit the cue ball at the porper spot. What jumping a chalk does is that it convinces you you can make the ball jump.
The key thought in jumping a chalk is to try to hold the cue as loose as you can, and to hit around the center of the cue ball. I like to remind myself to keep my elbow up so I do not scoop the ball.
After you can jump a chalk, try to jump two chalks. When you can do that, try jump over the gap between the edges of two balls. Do not try to jump a whole ball until you can do the above consistently.
I have seen so many people jumped their first jump shot at my booth in the US Open. Believe me, you can do it!
You may not realize it but you are jumping the ball higher than the height of a chalk when you break. If you dont believe me, try to put a piece of chalk about the width of 3 to 4 balls in front of your cue ball when you break and see if that chalk would move.
If you can jump a chalk with a full cue, you can do it with a jump cue.
Let me know how it goes.
Thank you.
Richard