Jim Stone shares his top tips for training servers to serve the seams, not the players.
The traditional serve zones are split into 6 zones, three in the front row and three in the back row. However, in traditional serve receive set-up there's a passer at each of those zones. So to learn to attack the seams instead, split the back row into four different zones, each one at a seam. This encourages your servers to make the passers move to pass the ball.