Using this floor liner is a breeze. Just place it in the front footwell of your 2015 - 2021 Subaru WRX or STI. The specially designed retention system will keep it in place. When there are fluids or debris on the liner, they will flow into the lower reservoir. To clean, simply lift the liner over the door sill and get rid of the mess. For maintenance, it's best to clean it regularly. You can use a mild soap and water solution to wipe it down. Avoid using harsh chemicals as they might damage the high - density material. This floor liner is designed to last, but taking good care of it will ensure it continues to protect your car's interior and maintain its resale value.