Running back and forth and side-to-side, bumping/setting to each other and/or bumping/setting to a target, diving for a ball, teamwork/trust exercises to determine who'd be a "team player," serving drills and slamming drills.
do approaches, you run like your going 2 spike it
go as low 2 the floor as you can and move around in that position
run around court, hitting balls thrown in random spots
hit a ball against a wall for your timing to get perfect
google for more! yeah
everytime you make a serve into the correct spot of the other side of the court. bumping the ball, the team would start in the back i would stand on a ladder and hit the ball to them and they need to bump the ball for a good set for the setter