Have everyone spread out evenly into a deep infield position. One player on first and I use another player for backup to the first baseman. Have an assistant be the catcher or you could use another player. Start the drill by coach saying ready. This is a que for getting all the players into a ready position. You then hit grounder or fly balls to them. They will need to be sure and call it if it is a fly ball. On grounders make sure they setup in the PFP (Perfect Fielding Position) and keep the ball in front of them. Once the catch is made a good throw to first base is then made. The first basemen then throws the ball to the catcher. If a ball is missed the player missing the ball runs and retrieves the ball runs back and rolls the ball into the backstop while everyone else continues on with the drill. After they all have received at least one ball hit to them I will then yell switch. At that time the player that is backing up the first baseman becomes the first baseman. The first baseman goes to where third would be and everyone else rotates toward first. I usually have punishments for trying to correct certain aspects of the drill. For example not getting ready, not getting in front of the ball, not using PFP, making bad throws to first ect. have to run a short distance and return to the drill. I also award players doing things correctly. PFP - Perfect Fielding Position - Glove foot forward. Other foot shoulder with apart at the inseam of the glove foot. Glove out in front and on the ground. Back parallel with the ground. Shoulders square with the hitter.