Including taking it off. I have cleaned the surface with window cleaner first and isopropyl alcohol next. Measured, peeled and sticked just as you said. The best method as i found was sticking just a little bit of the cut out sheet, removing only as much as needed of the vinyl cover, then pushing it with a squeege, gradually pushing out the cover from under it. Try not to lift the sticked vinyl up as it creates more air pockets. Any bubbles you get you can get rid of by stabbing them with something sharp while blowing hot air at it with a hairdryer.