The BOA Exfoliant is practically ageless and there is almost no shelf life for this product. It can be stored in its original packaging for years!
Just keep your BOA in its original packaging (pouch) and once you are ready to use it, remove it from the pouch and just rehydrate the product by dropping some water (cooled-down, boiled water) over the top of the stick and leaving it to soak in overnight. The product will be ready to go the next day.
If still dry, you can repeat this process and add more water to the clay.