This exercise demands at least 5 players, and at least 2 players at the starting position.

The ball starts with A, who throws to B.
Immediately after A runs behind B's line.
B throws to C and runs behind C's line.
C throws to D and runs behind D's line.
D returns the ball to the next player in A's former line.
A throws to B and so on....
It is important that the players follows the shown lanes and do not enter the lane of the ball