Brush with toothpaste. It's very useful. After brushing, dry it with a dry towel, wrap it in toilet paper and put it in a shoe box, and then put two packs of desiccant, and it will be fine. Remember to brush your teeth with a toothbrush and then rinse with water.

There are also small partners who respond to napkins. Don't use a wet tissue. I even tried an eraser before, but it didn't seem to work. In fact, what can be erased can be erased by touching it with your hand. But don't wipe it with anything that has touched water.