Scrub the skillet with steel wool or a stiff brush to remove loose rust
Wash with hot water and mild dish soap
Rinse thoroughly and dry immediately
Apply a paste of baking soda and water to rusted areas
Scrub again with steel wool or a non-scratch scrub pad
Rinse and dry completely
If rust remains, soak briefly in white vinegar mixed with water
Scrub the rusted spots after soaking
Rinse thoroughly to remove all vinegar
Dry the skillet right away
Heat the skillet on the stove for a few minutes to remove any remaining moisture
Apply a thin layer of cooking oil to the entire skillet
Bake the skillet upside down in the oven to re-season it
Repeat seasoning if needed
Store the skillet in a dry place