* Remove your back cover, battery, sim and memory card. Lever away the metal plate away at the points circled. It won't come away completely yet.
Sony Ericsson W902 disassembly stage 1
* Remove the Walkman sticker on the front of the phone to reveal two screws. Remove these screws.
Sony Ericsson W902 disassembly stage 2
* Run something like a credit card around the join of the front cover to release it.
Sony Ericsson W902 disassembly stage 3
* Lever the main body of the phone out with your plastic tool at the points circled, below.
Sony Ericsson W902 disassembly stage 4
* Your phone should now look like below.
Sony Ericsson W902 disassembly stage 5
* Turn the phone over. Circled is a ribbon connector. This attaches like a plug and socket. Simply pull it up, away from the phone, to unplug it. Then pull the black/green part in the direction shown by the arrows.
Sony Ericsson W902 disassembly stage 6
* Your phone should now look like below.
Sony Ericsson W902 disassembly stage 7
* Lift the part shown below from left to right. Two ribbons needs disconnecting (circled). Again, they attach like a plug and socket.
Sony Ericsson W902 disassembly stage 8
* Your phone should now look like below. Turn the phone over and lever the LCD screen away with your plastic tool. One of the ribbons you have just disconnected will slide through the back of the phone when you remove the LCD screen.
Sony Ericsson W902 disassembly stage 9
* Your phone should now look like below, with the LCD screen removed. Reverse the whole procedure for reassembly.
Sony Ericsson W902 disassembly stage 10
Source: www.formymobile.co.uk