This is the hardest part of the entire process.

You will see 4 metal tabs holding onto something. These are located on the top right, top left, bottom right, and bottom left. These hold onto each half of the potentiometer. CAREFULLY move those out of the way with either a dull x-acto knife, tweezers, or a flat head screwdriver.

Once you do this, carefully remove the dial. Behind it are three metal rods. DO. NOT. TOUCH. THESE. If you do, they may bend out of shape or break, and then you will have an even bigger problem.

The half you pulled out is a dial with a lot of parts that are conductive, and a lot of parts adjacent to them that are not conductive. Kind of like an optical illusion. The direction in which you turn this will affect the order in which the metal rods will conduct. This is how the volume is changed.

Get a Q-Tip and either electronics cleaner ot Isopropyl Alcohol and clean the reverse side of the dial (the optical illusion part).

When you are done, BE SUPER CAREFUL putting it back together. You should see a metal nub that sticks out. It must be facing upward.

The easiest way I have found works is by using small pliers and squeezing them back into place once the two halves are put together. Then, taking your flat head screwdriver, flattening them down flush with the potentiometer.