You do not ever have to wash your pack, if you take care to only apply oil in the center of the pack away from the seams. If you do prefer to wash your pack when it becomes very saturated with oil, usually after 10-12 treatments, you may do so. Soak overnight in hot water with 4 tbsp. of baking soda, and 1/2 tsp. of clean, natural dish soap. In the morning wring it out and hand wash with the healthy dish soap. Place on the outside of an old tea towel that you don’t mind ruining and press out the Castor Oil. Continue to do this until the outside has very little to no oily residue.