While oven is off, remove oven racks and anything else that may be housed in your oven (such as pizza stones or thermometers).

In bowl with baking soda, add water a tablespoon at a time until a spreadable, paste-like texture has been achieved.

Put on gloves; spread paste over all the surfaces of your oven (except any bare metal or heating elements). The paste may turn brown as you spread it around.

Let sit in oven overnight, or at least 12 hours.

Using damp cloth or spatula, remove baking soda paste. If there are any lingering spots, spray vinegar on them to help remove the paste.