Mark out a lines that is 10 metres apart. For example these two white lines in the photo.
After this place two throwers behind either side of each line. The throwers cannot pass this line.
Now everyone else must go between the catchers (between the 10metre lines)
Now it's the aim of the thrower to pass the ball between one another without the catchers catching the ball. However do not throw the ball metres into the air so it's physically uncatchable.
You only have one chance to catch the ball catchers, so if you juggle the ball and fail to catch it it doesn't count.
If a catcher does manage to catch the ball then swap with the last person to throw it.