Unplug the microwave
Remove the turntable and roller ring
Wash the turntable and roller ring with warm soapy water
Wipe loose crumbs and debris from the interior
Fill a microwave-safe bowl with water and add lemon juice or white vinegar
Heat the bowl for 3 to 5 minutes until the microwave steams up
Keep the door closed for a few minutes
Carefully remove the hot bowl
Wipe the interior walls, ceiling, floor, and door with a soft cloth or sponge
Use a non-abrasive cleaner for stubborn spots
Scrub corners and vents gently with a soft brush or cotton swab
Dry the interior with a clean cloth
Reinstall the turntable and roller ring
Leave the door open for a short time to air out the microwave