Remove screws with Phillips head screw driver. There are 2 screws that hold the lid cover that exposes the RAM.
Each screw is marked with RAM picture.
Press the small clips with the screwdriver to remove the RAM.
Slowly slide the new RAM into the slot until you hear the click sound. Make sure the teeth line up In the slot.
Put back the lid removed on step 1 and make sure the screws are fastened.
Before you preform this, make sure you purchase the correct RAM designed for your unit. Also make sure the operating system can handle it also. Good luck !