Using a Phillips head screwdriver, remove the screws shown in the image. They all have the letter "P" next to them.

Carefully unplug the connections shown.

Don't forget the display cable. It is slightly to the right of the Dell logo at the top.

Also, the wireless cables on the right side may prevent moving the upper case out of the way.

Once the screws have been removed and the connections unplugged, use the plastic opening tool to gently separate the panel from the lower case.