Adjust the machine so that your knees are in line with the rotating cams and lay face down with the pads resting on your lower legs just above your feet.
While keeping your torso firmly planted on the bench and holding onto the handles for support, curl the weight up as high as you can without allowing your upper legs to raise off the bench.
Pause briefly, and lower the weight back down until your legs are just short of being fully extended, and repeat.
