The easiest way to clean your shower curtains is to wash them in the washing machine using cold water. You can wash the shower curtain with other clothing, but make sure that they are similar colors, that you don't use bleach, and that you use cold water. DO NOT DRY IN THE DRYER. Hang them back up to let them air dry in the shower.
Don't replace your shower curtain or use expensive chemicals to clean it. Soak your shower curtains in water and baking soda to clean them.