Using these fender covers is super easy. First, make sure the surface of your WRX's fenders is clean and dry. Then, peel off the backing of the 3M adhesive on the covers. Carefully align the covers with your fenders and press them firmly into place. You don't need to drill or customize anything. As for maintenance, just wash them with mild soap and water regularly. Avoid using abrasive cleaners as they might damage the clear coat. Also, keep in mind that these are covers, not full fender replacements. Don't try to remove or re - attach them too often, as it might affect the adhesion of the 3M tape.