Easy to use out of the box. Each protector film has peel off layers on both sides. Remove one on the underside, align the film (it's a perfect fit for the Dell Steak 5 screen) and carefully lower it down from one end to the other, then pull off the upper layer. Only two tiny bubbles, which suggests I didn't clean the screen perfectly, but they don't show once the phone is switched on. So far the protector has worn well and saved the glass beneath. No problems using the phone screen either.