The coach sets a total of three targets areas, one for each shot of the player. Two of them are placed deap, one at in each corner, and a last one is placed shorter (watch video for placements of the targets).
Practicing with the coach:
The Coach is positioned a little bit in front of the baseline with his coaching basket. He starts by feeding the 1st ball deep (but not to deap) to the players forehand. This ball the player hits deep and cross-court.
The 2nd ball is to be fed short to the players backhand side. The player starts moving forward and hits a deep backhand slice approach into the target area, and continues moving forward.
Just before the Coach feeds the 3rd ball the player performs a split step (the coach should always remember the player should he forget it). This 3rd ball goes to the players forehand, which he volleys with an angle to the final target area.
do this drill for about 10 (or 30 balls), give the player a little rest and repeat.
This drill can be done in a group lesson as well. I would say a maximum of 4 players, to avoid long waiting times.
Practicing with friends:
Same concept. Just rotate the feeder and make sure you have enough balls.