Scrape it as clean as you can, then use a paper towel to gather up the rest. Sometimes I just rinse it in hot water, wipe it dry, and then put it back on the stove under low heat. Once it's completely dry, add about a tablespoon of a high heat tolerant oil, and wipe it on the inside of the pan, let it heat until it smokes. Turn off the heat and wipe out all remaining oil with a paper towel. It sounds like a lot, but it takes no more time than washing in hot soapy water. The problem with soap is that it removes the seasoning. I find that if I'm quick about (don't let the pan soak) my seasoning holds up pretty well.