- Put food colouring in each of the small clear containers and add a little water to each
- Fill the big container with water 2/3 full
- Top it with a generous amount of shaving foam
- Add drops of your coloured water onto the shaving foam with a spoon or pipette
- Watch the colours mix through the shaving foam and into the water
- Try using different colours to see how they mix
- Remember to wear an apron or something that you don't mind getting messy!