Start: Attach a stirrup handle to the low pulley. Grab the handle with your nondominant hand and stand sideways to the cable column so your dominant side is toward the weight stack. Hold the handle near your stack-side hip, with your elbow slightly bent, as if your were about to pull a sword from a scabbard.
Finish: Raise the handle up and across your body until your arm is parallel to the floor and the cable is right against your body. Pause, then return to the starting position. Finish the set with that arm, then switch and repeat with your other arm.
Attach the stirrup handles to both low cables of the crossover machine. Grab the handles with a crossover grip and stand between the towers. Lean forward slightly and execute the move the same way you would with one arm.