Self-cleaning ovens have a specialized feature that uses high heat to remove grime and built up food spills. Although it sounds like a relatively hands-off process, you must properly prepare your oven before using the self-cleaning feature. If not, your baked-on stains will remain and you could damage parts of your oven. Your oven may not be able to handle all stubborn baked-on stains, so you may still have to manually remove those afterwards.
Add 4 tablespoons of baking soda into 1/2 cup hot water and mix them until it forms a thick paste. Stir in an extra 2 tablespoons of baking soda if the mixture is too thin. Smooth the paste onto any baked-on stains and let it soak into the stains for at least 15 minutes.
Use a scrub brush or pad to forcefully rub the paste until the baked-on particles start to loosen and come off. Soak a sponge in warm water, then wipe it across the areas to get rid of any of the paste that remains so the oven doesn't smoke during the self-cleaning cycle.
Slide your oven racks out and remove them from the oven or else they could become discolored during the self-cleaning. Set your oven to the self-cleaning cycle and let it run for the length of time specified for your particular model.
Apply additional baking soda paste to the oven racks and scrub away any burnt food stains while the oven is self-cleaning. Rinse them thoroughly and set them aside until the oven is finished cleaning.
Wait until your oven is completely cooled down after it is done self-cleaning. Soak a sponge in warm water and use it to remove the loose ash from the heated baked-on stains.
Slide the cleaned oven racks back into place. Wait until your oven is thoroughly cooled and dried before using it again.