To install decorative window film, first measure the window's length and width. Clean the glass. Cut the decorative window film to fit the window and then hold the film up to the window with the release liner facing away from the glass. Remove the release liner from the film and then spray it down with wet adhesive solution to ensure the film sticks securely to the glass. Lay this side of the film flush against the glass.
For larger windows, have another person help hold the decorative film up against the window. Before laying the film, check the decorative window film for any dry spots. Be generous with the application of the wet adhesive solution, which helps keep the film from drying out before application or sticking to the window's glass before it has been properly positioned.
To remove the release liner properly without damaging the decorative window film, use a thin sharp object like a finger nail or small knife to peel back the plastic liner. When the film is against the window, use a squeegee to apply strong even pressure to ensure it dries evenly and flatly without any air bubbles, cracks or creases. After the film has dried and stuck, trim away any excess film from the window.