Step 1. The outside throw means that you throw the second ball back over the first one. Regular throws in the 3-ball cascade (Lesson 1) are called inside throws in contrast.
Step 2. Make a single outside throw in a three-ball cascade (see the red ball). First learn one side, then the other.
Step 3: Tennis. Use the outside throw every three times. You are done, or you can continue with other variations below.
Half Shower. One hand is throwing outside, the other throwing inside. Learn both sides separately.
Reverse Cascade. All throws are outside throws. If you would run a video of the three-ball cascade backwards, it would look like this. This pattern is easy to try, but difficult to run continuously.
Arches. Use the outside throw twice every three times (red ball does all the inside throws). Note how each ball has its own arch, one on top of each other. (This is a rather difficult pattern and it might be better to skip it for now and return to it later.)