Using these Subaru side skirt extensions is easy. First, make sure your vehicle is clean where the extensions will be installed. Then, use the included hardware to attach the side skirts under the existing ones. You may need a basic set of tools for this job. As for maintenance, regularly wash your car to keep the side skirts clean. Avoid driving over rough terrain or hitting curbs as this could cause further damage to the already slightly bent side skirts. Remember, these are clearance items and are non - returnable, so handle them with care during installation and use.