Spray the surface with white vinegar or a vinegar-and-water mix
Let it sit for 10 to 15 minutes
Scrub with a non-abrasive sponge or brush
Rinse with warm water
Apply baking soda paste for stubborn buildup
Scrub again and rinse thoroughly
Use a commercial soap scum remover if needed
Wipe the surface dry with a microfiber cloth
Repeat as necessary
Prevent buildup by wiping surfaces after each use