How do you properly season a cast iron pan?

To properly season a cast iron pan, first wash it with warm, soapy water and dry it completely. Then, apply a thin layer of vegetable oil or shortening to the pan, making sure to coat the entire surface, including the handle. Place the pan upside down in an oven set to 350F (175C) and bake it for about an hour. Let it cool before using. Repeat this process a few times to build up a good seasoning layer.