Overview

Pick up a tennis ball. If there aren't any tennis balls at hand, roll a towel or t-shirt into a tennis ball-esque shape. Tie it up with a rubber band, for a more realistic effect. If there's absolutely nothing nearby that can serve as a tennis ball ersatz, just visualize one. Okay, now take the ball/t-shirt with rubber band/visualized round object and hold it in your hand. Now squeeze. Harder! Even harder! Okay, keep squeezing! Until your fingers hurt! Yes! Now let go. Feels good, huh? Now practice letting go in other parts of your life, for the rest of the day.