Use a stud finder to locate the studs on the wall under the cabinets. Tap the wall lightly with a hammer if you don’t have a stud finder.
Hold the mounting plate for the microwave against the wall and mark the holes in the center of the studs; you need at least one stud.
Drill a hole through each of the markings that corresponds with the size of the bolts that are included with your brand of microwave. Bolt the mounting bracket to the wall, using the bolts in your package, so it is secure.
Hold the template that comes with the microwave against the bottom of the cabinet, and mark where you should drill the holes for mounting screws and the power cord.
Drill the holes through the bottom of the cabinet according to your template. Set the microwave onto the bracket and feed the power cord through the hole you’ve drilled.
Open the cabinet and place the self-aligning screws down through the top, into the microwave. Screw them in so the microwave is secure.