I followed all the instructions on the packaging and watched the YouTube video prior to attempting the application. I had help to hold the film while I sprayed it as I was applying to slider doors which is a large area to cover. The first one took approximately 40 mins in total using the tools supplied. I bought a larger plastic tool to help remove the air bubbles and had the job done in under 10 minutes, saved me a world of pain and effort. The tool included is the size of a credit card, I would strongly recommend buying a bigger version to save yourself a lot of stress and effort. The final result is fantastic, very happy with the finish and function.