To add memory to a computer, turn it off, unplug it and allow it to discharge. Then, remove old RAM modules and replace them with higher-capacity ones. Laptop and desktop RAM require similar procedures, but changing a laptop's RAM is much more difficult.
Desktop computers have a removable cover, allowing access to the whole interior. Use an antistatic wrist bracelet to dissipate static charge before touching anything inside the computer to avoid the risk of serious injury. Look for the RAM modules, which should be long, thin parallel boards connected to the motherboard. Grip them by the edges and gently ease them out, and then place the new ones in the slots. Ensure that they are seated firmly. Some models have latches that click into place.
To change a laptop's RAM, turn off the laptop, unplug it and remove the battery. Discharge and remove the RAM cover. Consult the user's manual for its exact location. Then, flip up the small latch and remove the RAM module. Insert the new one carefully, because laptop parts are easily damaged. Gently move the card into the slot, holding it at an upward angle, and press it into place before reengaging the latch.
Replace the computers' covers, restore the power and turn the computers on. The BIOS should recognize the new RAM module. If possible, use the same brand as the original RAM to avoid compatibility issues.