After the computer base (#1) is facing up, use a Philips screwdriver to remove the two captive screws (#2) which hold the base panel (#3) down.
Then, use a spudger (#4) to lift up the panel. You can also use your fingernail to lift it as well.
After the front has been lifted up a bit, the non-screw side of the panel will need to be slid forward a little to finish lifting out the base panel from the computer.
You don't need to disconnect the laptop's battery if you are only replacing the back panel: only perform this step if you will be handling or replacing the electrical components of the computer.
Disconnect the battery cable from the system board by pulling up on the battery connector (#1).
Turn the computer back over and open the display to the point where you can press the power button.
Press and hold the power button for 4 seconds to ground the system board so that you can safely remove components such as the RAM.
Slide the memory module firmly into the slot at an angle and press the memory module down until it clicks into place. Do this individually for each memory module that is replaced.
NOTE : If you do not hear the click, remove the memory module and reinstall it.
Remove the keyboard-backlight cable, keyboard cable, and macro-keys cable from the routing guides (the small plastic tabs) on the computer base.
Do not force the cables out of the system board without lifting up the latches that hold them down first. Forcing out cables could result in them snaping or tearing, rendering them unusable.
You do not need to remove the hard drive to remove the battery, but it is advisable that you do so if you are concerned about dropping the computer while removing the battery.
Remove all 15 screws which hold down the computer base. Two screws are located near the RAM slot, while the others are situated mostly around the outside of the computer.
Open the computer's display and lay the computer down on the back of its open display.
Using your finger or a screwdriver, push inside the palm rest release hole (#3 in image 1) to release the palm rest from the tabs that hold it down.
Using a plastic scribe, pry up along the edges of the palm-rest assembly. After the palm rest is no longer attached to the computer via any tabs, try lifting up the palm-rest assembly.
Make sure that no cables or other fragile objects are still attached to the palm-rest assembly as you pull it out.