Put a bowl of water in microwave and turn microwave on for 3 minutes, then wipe the dirt off a quick as possible and if the water and heat starts to dry on the walls of the microwave…just turn on the microwave again for another 2 mins; to basically get the heat and water to reactivate and just continue to wipe clean. This does work, also put your glass plate in the dishwasher every day or hand wash it every day, usually the last dish cycle of the day so is clean for the in the morning. No only does steam kill the germs, but you dont have to use harsh chemicals. I would recommend every so often after you use the steam cleaning option, to use a disinectant like clorox/water mixture and let air dry with microwave door opening. Use your own judgment for when and how often you decide to do this. Happy Cleaning