I LOVE my clay pots (I have 2)! I clean my sink well using antibacterial dish soap and rinse well and soak the pot in there. I usually soak the pot for half an hour because the recipes I make require some assembly time and I don't want the pot to get dry. ... View related article.
Try a product called "Oops". I have found it at True Value Hardware and Shopko. This product is great, it will take off the paint but not damage the leather. I learned about it from my sister when she accidently got white paint on the seat of her husband's Harley Davidson motorcycle (yes it was already dry by the time we noticed). She didn't even flinch, just got the Oops, put a little on a rag and wiped it off!
Since them, we always have a can of it in our house (also works great at removing adhesive from things). ... View related article.