Guitar pedals in constant use will burn battery very quickly. Without prior knowledge and/or an instruction booklet, changing batteries could be tricky. Follow these seven steps and this procedure will soon become a piece of cake.
Hold the guitar pedal in your dominant hand. While your thumb grasps the base, the rest of your hand presses down on the foot trigger.
When fully pressed down, use your other hand to twist the black knob at the front of the guitar pedal.
Do not twist the knob off, but after a few twists, you should be able to lift the foot trigger up.
Lift the foot trigger up and you will be exposed to the interior design of the guitar pedal.
Detach, and discard, the current battery from its holders inside.
Take the new battery and connect it to the holders. (NOTE - the insides of guitar pedals contain springs. If the spring falls off, it is not the end of the world. Simply re-attach the spring before closing the pedal).
Lower the foot trigger and press down again. Once in the fully pressed position, twist the black knob back to its original tightness.
Test the pedal by plugging it in. Assuming it works, rock out!
The black knob is very tiny and can easily be misplaced. When changing the battery, try to do so on a bright surface or counter or merely make sure to place the knob in a nearby place, easy to remember.