Wash the skillet with warm water and a small amount of mild soap
Scrub off any rust or residue
Dry the skillet completely
Preheat the oven to 450°F to 500°F
Apply a very thin layer of cooking oil to all surfaces of the skillet
Wipe off all excess oil until it looks almost dry
Place the skillet upside down on the middle oven rack
Put a baking sheet or foil on the lower rack to catch drips
Bake for 1 hour
Turn off the oven and let the skillet cool inside
Repeat the oiling and baking process 2 to 3 times for a stronger seasoning
Use the skillet regularly and dry it after each wash