I followed the installation instructions on the enclosed sheet, not the video. The difference being that the video suggested removing the protective film before offering the film to the window, whereas the instruction sheet suggested offering the film to the window, back to front, removing the protective film in situ, & finally reversing the film & positioning on the glass. It took some time & care, but the result is fine. To help me identify which side was which I separated the two layers at one corner, & marked the clear protective film with a felt tip marker. (I was afraid of ending up with the adhesive side of the film facing out!)