Place the the mid-frame over the motherboard.

Using Philips #000 screwdriver, secure the three golden 3 mm screws of the mid-frame onto the motherboard.

When placing the mid-frame onto the motherboard, the bumper button may come loose. To reattach the bumper button, first insert the spring on the bumper button into the groove located on the top left side of the Joy-Con, then insert the right side of the bumper button into the Joy-Con.