You can clean your small microwave using several articles, including lemon, vinegar, baking soda, dish soap, or melamine foam sponges. The easiest option is to go for dish soap. Mix dish soap and warm water inside a bowl. The turntable and interior glass plate should be removed. Wash the glass plate manually using dish soap. Then make use of the soapy sponge for scrubbing the interior of your microwave. Keep rinsing and repeating the same process until your microwave is clean. You can use a scrubbing brush for a more stubborn stain.