It's easy to make your own foaming soap in all different scent combinations. The special cap turns the soap into foam that spreads easier and is more economical to use. How to Make Foaming Soap: 1. 4 oz. (or fill bottle half way) with liquid soap base (we like a thin base like our castile) 2. Add 20 drops of fragrance or essential oil 3. Fill remaining space in bottle with distilled water (leave enough head room for cap to fit without over flowing) 4. Label and enjoy! You can also add hydrosol instead of water for botanical foaming soap or add a drop of liquid soap dye for some color if desired. Have fun!