Clean inner and outer surfaces thoroughly to eliminate contaminants or debris. Best to apply when temperatures are above 60 degrees F. Remove liner from strip. Grab end and apply to starting point on the outside of door using your finger or thumbs. Apply the remainder of the strip using gentle pressure. Try not to stretch or pull the film while applying. This will ensure a straighter line. Once the film is applied to the outside surface, you can use your fingers to apply around the edge and onto the inner surface. Once the strips are applied, take a razor blade and lightly score the outside layers of the film and then peel away the excess. All done!