The main function of shaving foam is to make the mud have foaming effect, and add borax water to solidify the liquid. The amount of water added will determine the hardness of the foaming. If the foaming glue is hard, add more water. If you feel dry, you can add some glycerin, which will be more comfortable to play with. If the foaming glue dries after playing for a while, you can add glycerin and glue to mix, and the foaming glue can become soft again.
If there is no shaving foam at home, add shampoo and shower gel, or facial cleanser and foam hand sanitizer, and the foaming glue will be sticky.