You'd better watch an installation video on YouTuBe, which will help you to be faster and accurate Installation screen. 1: Open the package and check whether the screen is broken or damaged at the first time. 2: Please keep your phone power off when assembling. 3:Do not disconnect the connector by hand, this will damage the cable, please use the blue spudger. 4: There are different sizes and length screws when you replace your iPhone LCD Assembly, please remark each screw and put them in the original place (VERY IMPORTANT). Otherwise the screen will be easy broken if you put the screw in the wrong place. 5. The screen does not light up after a period of use. This is because the cable is loose, reconnect the cable tightly to solve this problem. 6. Touch is not sensitive or the letter keyboard jumps randomly.Please disconnect the battery again for a period of time and then connect to charge and restart.