Oven: The oven should not be used for 24 hours. Then you must clean it thoroughly and, if it is a self-cleaning oven, you run one self-cleaning cycle and the oven is Kosher for Pesach. If it is not a self-cleaning oven, after you thoroughly clean it, let the oven run on the highest temperature setting for approximately one hour, including the racks, then the oven is Kosher for Pesach.
Microwave: Take a bowl of water, with some detergent or soap in it, and then let it boil in the microwave until the microwave walls are filled with its steam. The vapor penetrates the walls rendering the microwave Kosher for Pesach. (If you can't do this and you need to use a year round microwave for Pesach, cover completely the food with a container or Ziploc products, Saran wrap or any other hermetic microwavable covers).
Refrigerator/freezer: Clean it and wash thoroughly each of its parts, making sure there are not chametz left-overs stored or stuck in its walls.
Satire: How to cut the Matza in two exact halves? (a Japanese tip!)
Rabbi Yosef Bitton. YMJC | 130 Steamboat Rd. | Great Neck | NY | 11024