Drain last meal,scrape it(shouldn’t have to)wipe it, rinse it, h2o only, dry it!
http://www.wikihow.com/Season-a-Cast-Iron-Skillet
A GF washed mine one time and had to preseason the darn thing all over.
The skillet that is!
The first and only skillet I ever had was washed in the dishwasher after the first time I used it. When I took it out the next day, it was all rusted so I threw it away and switched to teflon covered pans......lol!
With that being said, what’s wrong with teflon covered pans?
That's the worst thing a woman can do to a man with a skillet.
I use electrolysis to clean the old coating off altogether.
My set up is a large storage tub, a 12"X 20" piece of 1/4" plate as the anode, and a 24 volt charger with 2 car batteries in series.
Once I have the items cleaned (it has taken as long as 3 weeks, but the results are worth it) I start the re-seasoning process.
I start by washing the item to be seasoned thoroughly in soap and water, then dry it as well as I can. Then the item is immediately placed into a 550* oven for an hour. This is to prevent that super-light rust that forms in minutes in this area. Every half-hour thereafter I use a natural fiber cloth to wipe a SUPER-THIN coating of FLAXSEED OIL on the pan, making sure there is good coverage but NO puddling or large amounts of oil anywhere.
The flaxseed oil has a low smoke point, so it reacts quickly with the pan to form your coating. The natural fiber cloth is so that your pan doesn't get a layer of rayon/nylon/polyester blend stuck to it rather than the desired oil coating.
While linseed oil and flaxseed oil are essentially the same, I would rather use a FOOD GRADE oil rather than an industrial product on something I'm cooking on. I get mine from the local organic grocery, but most vitamin shops should have it.