Step 1: Remove eight screws on the back (🔴) and remove the cover. Step 2: Unplug the battery (🟠) and remove additional four screws (🔴). Step 3: Take out the old battery and put in the new one. Step 4: Screw the four battery screws back in (🔴) and connect the battery to the mainboard (🟠). Step 5: Put the cover back on and screw the eight screws back in (🔴).