Check the potato for soft spots, cracks or withering. Be sure the "eyes" have not sprouted. If the skin has a greenish tinge, do not buy it. Greenish skin means the potato was exposed to bright light too long. Store for up to 2 weeks in a cool, dark place (50 degrees F to 55 degrees F).
Scrub well with a vegetable brush. Prick each potato with a fork several times. Contrary to popular practice, potatoes should not be wrapped in foil before baking; this prevents them from becoming fluffy. Cook, unwrapped, at 400 degrees F for 45 to 60 minutes. Serve with herbed butter, sour cream, salsa or grated cheddar cheese.