Over time, Plexiglas can become stained, yellowed and difficult to see through. This is often the result of sun damage as well as dirt, dust and oil buildup. Plexiglas is more difficult to clean than other plastic surfaces since it absorbs moisture and binds dust together. This creates a grimy, yellowed surface that is unattractive and difficult to clean. Whether you want to clean your Plexiglas windows or get rid of the yellow tint on your car's headlights, the key is to use a nonabrasive cleaner and gently scrub.
Put several drops of dishwashing liquid soap on a sponge or soft cloth. Any type of sponge will work, but refrain from using metal-based sponges (such as steel wool) since they will scratch Plexiglas.
Run the soaped-up sponge under water and create a nice lather
Scrub the Plexiglas surface gently. Start at the top and work your way down to prevent going over the same area multiple times.
Rinse your sponge frequently. Add more soap and create new lathers each time you rinse.
Rinse the Plexiglas surface with water. Once you've finished rinsing, soak up the water with a clean, soft, lint-free cloth.