Well before the invention of oil-based paints, a much more simple and organic type of paint was used to create numerous famous works of art. Botticelli and Wyeth were just two of those artists who have painted with this age-old style that has been in use since ancient Egypt. This simple blend of pigment, water and egg yolk continues into the 21st century. Tempera painting is alive and well, and while traditional artists still use egg yolk in their paints, many companies have substituted other binding agents to make the product safer and longer lasting. One benefit of tempera painting over oil painting is the ease of the cleanup process.
Move to the nearest sink or to a bowl of warm water if one is available. Tempera paint is easiest to wash when it's wet. Use warm water, but not so hot as to cause burns.
Apply a liberal amount of dish soap if the paint does not come off easily in water or has already dried. Be sure to apply a hand lotion afterward if you have sensitive skin; dish soap can dry out your hands. Use hand towels to dry off before you go back to painting so you don't add more water to the mixture.
Clean your hands with a baby wipe if no source of water is readily available. If the tempera paint isn't coming all the way off, don't worry. Tempera paint has been used as body paint for hundreds of years and is safe to leave on the skin until you have a sink nearby. It will also eventually begin to flake and fall off on its own if left on your skin.