Turn off the dedicated breaker powering the microwave at the main electrical panel in your house, laundry room or garage.
Open the cabinet doors directly above the microwave. Place a step stool under the open cabinet doors. Remove any contents in the cabinet.
Unplug the microwave's power cord. Have a friend or family member hold the microwave from the bottom to support it while you begin to dismount it from the cabinet.
Unfasten the retaining screws or bolts with a screwdriver or wrench, whichever is applicable to free the microwave and gain access to the hood.
Unfasten the hood from the microwave using a screwdriver. Put the hood aside and remount the microwave, if desired. Fasten the retaining screws or bolts back in place.
Plug the microwave back in and turn the circuit breaker back on.