Tools required: Phillips screwdriver, plastic tool such as a guitar plectrum or credit card, suction cup, needle/drawing pin/paperclip or something similar. First push something like a paper clip into the hole at the top of the phone. This will release the sim holder. With the sim holder removed, your phone will look like below. At the other end of the phone you'll see two screws. Remove these screws. Release all ribbons. Remove the screws on each side of the screen. Now remove the screw circled in the picture below. Slide something like a credit card under the LCD screen to release it. You should now have the LCD screen removed. Reverse the whole procedure for reassembly.
