Do you have a recipe that just for some reason tends to stick to your crock pot? Simply take your nonstick cooking spray, and give a light quick spray to the inside of your crock pot. This will help prevent any food or sauces from sticking and burning to the edges of your crock pot.
As an alternative, you can also use a slow cooker bag or a make your own with a roasting bag. Do be aware though that these can be expensive, and they still often tend to leak, so you cannot just pull out the bag and have a sparkly clean crock pot underneath, you will still need to clean it.