Take out the Card Tray. Heat up the edge. Focus on the bottom. Use plastic or poker card to open the Back Cover. Insert the card to gap and remove the Back Cover. Release the Battery flex cable and Power Button flex cable. Rear Camera flex cable. Remove Rear Camera. Release the screw here and remove the bracket. Release the Front Camera flex cable. And remove it. Release the Headphone Jack flex cable. Undo 5 screws. Loosen the plastic bracket, and remove it. Release the Charging Port flex cable and LCD flex cable. Take out the Microphone PCB Board. Remove the Motherboard. Pull out the Battery Sticker. Remove the worn battery. There are two protective film. Pink and blue. We just need about 3CM. and put it on the frame. Peel off the blue film. Install the new Battery. Mind the flex cable. Connect the Charging Port and LCD Screen flex cable. Put back the bracket. Tighten up 5 screws. Connect the Battery flex cable and Power Button flex cable. Headphone Jack flex cable. Put back the Back Camera. and then Front Camera. Put back the shield. Tighten up the screw. Put on the Back Cover Sticker. Make the sticker adhere to the Back Cover. Remove the protective film. Put back the back cover. Make it match well to the phone. Put back the SIM Card Tray.