Wash the skillet with warm water and a small amount of mild dish soap
Scrub the rust with steel wool, a scouring pad, or a stiff brush
Use coarse salt with a little water or oil as an abrasive if needed
Rinse and dry the skillet completely
Remove any remaining moisture by heating the skillet on the stove or in the oven
Apply a thin, even layer of cooking oil to the entire skillet
Bake the skillet upside down in the oven at 450–500°F for about 1 hour
Let it cool in the oven
Repeat the oiling and baking process if rust remains
Store the skillet in a dry place after use
Avoid soaking the skillet in water for long periods