The players must decide which teammate they will support on the pass or which ball they will try to tackle or intercept. When they are going to receive or gain control of a ball, they may need to call to a player that is not looking to support them. During some period of play the GKs should be restricted to playing with their feet. Balls out of play can be restarted by dribbling in, pass ins, throw-ins or chips to other side of the area. Be sure that the players communicate when an air ball is coming, else there may be a few unintentional headers.
Apparent disorder is a product of control.
Here's a base exercise that can be built upon. This also could be a nice pre-game shooting exercise. After A drops, A should spin away from the pass and turn towards goal. After B plays to the checking A, he overlaps towards the middle to receive and shoot. On the return pass from B, A drops to C who has overlapped A towards the middle.