On any hit into the gaps or down the lines with no runners on base and the outfielders are unable to cut it off, your middle infield should automatically move into double cutoff position for a throw to third base.
Have the infielder closest to the ball move out and be the first person in line for the throw. The other middle infielder should line up about 10 yards behind the first infielder. I've seen many double cuts where the infielders are standing about 5 feet away from each other. That doesn't do much of anything. The infielders need to be spaced so together they can cover the most space on the throw coming in.
The first baseman has the important role of trailing the hitter to second base. If the runner stops between second and third the first baseman has to be in position to get a throw at second either from the cutoff or in a run down situation.