How do you clean new a cast iron skillet before use?

the procedure is called blanching.get skillet very hot then wipe with clean fresh cooking oil.

I love my cast iron skillets. After they have been cured (blanched?) they must be maintained by keeping them oiled. If the oven is still hot after cooking I coat them with oil and let them sit in there until the oven and pan have cooled. This keeps them for the next time I need them. If you make things that are acidic (like spaghetti sauce) in them it will remove the oil coating.