Tips to clean a microwave

This time I'll give you tips to clean a microwave and leave it clean, free of grease and unwanted odors. (This tips are contribution of our house cleaning maids from Fort Lauderdale, Coral Springs and Hollywood, Florida.)
Clean the microwave is not a simple task. We have to clean the microwave by following certain recommendations and steps to avoid damage. Most microwave ovens have special paintings inside, must not damage, as this may void the warranty of the unit and cause malfunction in its operation.