I have taught juggling to hundreds of people. I am quite confident that I figured out an effective way of teaching it – and I decided I might also share it here.
Before we begin, I must warn you: Juggling is highly addictive. I do not take any responsibility for you becoming addicted and all its consequences (eg. seeing all objects surrounding you as juggling props)!
Cascade is the essential, and the easiest trick with three balls. I like to break it down into three steps.
Start with one ball in your dominant hand, standing with your elbows bent 90 degrees and your palms facing up.
Toss the ball to the other hand with an upward movement of the forearm (not the wrist, not the whole arm).
Both elbows should be kept next to your hips. The peak of the throw trajectory should be at eye level, and the angle of the throw should be so that the ball lands where your weaker hand is waiting.
When catching, do not reach for the ball; simply wait for it to fall into your palm. If your throw is inaccurate, make a step to move your body rather than catching the ball in uncomfortable positions.
After you learn how to do the basic throw, we will add the second ball and learn what we call the exchange. This is a basic juggling move named after the fact that the two balls change their positions.
Take two balls (ideally of different colors), and hold one in each hand. Throw the first ball (yellow) from your dominant hand just like in Step 1.
Once the ball is at the peak of its trajectory, throw the second ball (orange) from your weaker hand "underneath" the first one (jugglers call this the inverse throw). In other words, the trajectories are not identical—that would cause the balls to collide mid-air—but each trajectory is shifted to the catching hand side.
Catch the first ball (yellow) with your weaker hand.
Catch the second ball (orange) with your dominant hand.
That was the exchange. You can also try switching the sides: that is making the first throw from your weaker hand followed by the second throw from your dominant hand. Once you can do the exchange comfortably on both sides, there is nothing to stop you from going for the cascade.
Finally, the part that we were practicing for, is here! Take three balls, two in your dominant hand, one in your weaker hand.
Hold the two balls so that you hold one (yellow) with your thumb, index and middle finger, and the other (red) with your ring finger and pinkie.
Toss the first ball (yellow) from your dominant hand.
Just like in the exchange, throw the second ball (orange) from your weaker hand when the first ball (yellow) is around eye level.
Catch the first ball (yellow) in your weaker hand.
When the second ball (orange) is around eye level, throw the third ball (red) from your dominant hand. Notice that this is again just like the exchange, only on the other side.
Catch the second ball (orange) in your dominant hand.
Now, repeat the last four positions (over and over) – and you are officially juggling the 3-ball cascade! I mean, of course you will need hundreds of tries before you juggle the cascade solidly. Don't be discouraged by drops, even good jugglers drop all the time when practicing!
I collected a handful of tips for beginner jugglers.
Let me explain what this silly-sounding tip actually means. Shower is the juggling pattern in which you throw from one hand and zip from the other – forming a (roughly) circular shape. Even though I like this trick a lot, I do not recommend you learning it before you can do the cascade well.
Non-jugglers often intuitively start with a 2-ball shower – throwing a ball from their right hand, then zipping the second ball from left to right, and then catching the thrown ball to their left. It is easier than the exchange (there is only one actual throw), and by doing it you are not learning the important aspect of juggling: focusing on more than one ball in the air. So, practice the exchange instead, forget about the shower... and maybe come back to it a few days later, when you feel like it is the right time :)
If you are tired of picking balls from the ground, you can try to practice juggling while kneeling or standing near bed, facing it. That way you don't have to bend each time you drop a ball! Another option is to learn to kick them up with your feet (a tutorial for that is coming soon!).
Big goals often seem unreachable, and that's why it is better to break them down to steps, and then focus on the small steps rather than the ultimate goal far away. Applying this general advice to juggling can be very helpful to keep yourself motivated.
For example, if going from the exchange to the cascade feels like a step too big, you can divide it into smaller steps by stopping at a certain number of throws. For example, start with three throws. When you master that, go for four throws, then five, and so on.
Juggling beanbags that fit nicely into your hands and aren't slippery can make it a lot easier. And as a bonus, juggling is a lot more enjoyable with some good-looking equipment!