To clean a cast iron skillet, you would clean it like any other pan, except you would want to use a mild scrubbing sponge. If there is something stuck in it, then you most likely didn’t have it seasoned properly. It’s best to use mild soap for your pan and not put it in a dishwasher. To season your pan, just use a small amount of cooking oil to rub over the inside of your pan. Never store a cast iron pan without making sure it’s seasoned.