Your head is resting in your hands, elbows are wide and stay that way, eyes are on the ceiling. Exhale on each contraction. First be sure you have determined the proper weight increment. This should not be super hard but enough to do about 20 repetitions and need a break. Set your chest on the pad adjusting the machine to fit your body.
Feet are back and tucked under ankle pads.
Hands are on the grips in front. Concentrate on the abdominal muscles and lower the pad by pulling down and crunching with your abs. Do not drop the weight or come all the way up until your set is done. Hold the contracted position and pulse small repetitive movements before releasing. Grab the cable with both hands, kneel down on the floor, position the handle of the cable about the top of your head.