All you need is baking soda, black food coloring (found in baking aisle), and a bit of water. It feels almost exactly like real dirt! Slowly add water until the baking soda is slightly moist You want it to be damp and moldable but not wet. If you add to much water it will turn to liquid which is actually a good thing for after the play but not before! Baking soda dissolves in water making it 100% tub time safe. It won't clog the drains and will actually clean them!