Smart Ash is a black powder (read potential outfit ruiner). If you’re using an electric toothbrush, don’t turn it on until the bristles are in your mouth. Wow, that would be a mess.
If you’re worried about younger kids making a mess, have them brush with Smart Ash while in the tub. If you’re worried about you making a mess, try brushing in the shower
Dampen toothbrush and dip bristles into powder, a little goes a long way.
Gently brush your teeth for 2 minutes. Don’t cheat!
Brush again with water to remove residue. Spit close to drain with meager force to minimize mess.