You should begin your daily workout with this procedure. This is not really an exercise, but a prerequisite. What the "hot towel warm-up" does, is draws blood to the area of your penis, increasing the blood flow and making the skin slightly elastic. This also ensures a good grip for the exercises you will be performing.

Soak a washcloth in warm-to-hot water, then wring out. Take the cloth and wrap it around the shaft of your penis (either flaccid or erect). Hold it there a minute, then repeat a couple of times. Dry off your penis well.