Four Ball Shower
The Four Ball Shower is just as
it sounds: a Shower pattern with four balls. Relative to the Three Ball
Shower, this trick has throws that are higher and faster, making the
Four Ball Shower significantly more difficult than its little brother.
To learn the Four Ball Shower, it is best to start with two balls in your dominant hand, and one ball in your non-dominant. Make a high throw (a foot or more above your head) from your dominant hand, and then quickly follow with a second high throw from your dominant hand along with a near simultaneous horizontal pass from your non-dominant hand. As the first ball thrown approaches your non-dominant hand, throw your last ball (the one that was passed) along the same path as the previous two. Then catch all the balls. If done right, there should be a brief period of time after the last throw where there are no balls in any of your hands.
Practice this until you are able to execute all throws accurately and with consistent timing. Then, take two balls in each hand, and do the exact same set of throws as above, except pair the last throw of the previous step with another horizontal pass using the new fourth ball.
And that's pretty much all there is to the Four Ball Shower. Just keep adding in high throws paired with horizontal passes and, as you become more comfortable, you will gradually be able to run the pattern for longer periods of time.