Pull up on the metal clamp of the lock.
Turn the combination portion clockwise until you hear a click sound. Stop at the number where you hear the click and then turn the dial to the right two more numerical places. This is the first number of the three-number combination.
Continue holding the metal clamp up and tight, and turn the dial to the left until it stops. The number it stops on is your second number.
Turn the dial to the right as you continue to hold up on your clamp. Continue spinning the dial to the right until the lock opens. The number the lock opens on is your third number.
Use bolt cutters to cut the combination lock. Generally, bolt cutters will cut through the combination lock's metal without too much trouble.
Try banging a hammer into the top of the combination lock. You should aim the hammer directly on top of the curved lock portion. If the pressure is applied properly, it will sometimes release the lock.