Never handle dry pigment without the use of a dust mask or respirator . Dry pigment can be toxic if breathed. If need be add a small amount of water to make the paint more fluid. Try not to add too much because a solution that is either too thin or too thick will result in cracking. Close up container and repeat procedure for all colors to be used.
Egg tempera works best on a finely sanded oil-gessoed or rabbitskin glue prepared wooden panel.
An excellent product to use for the painting ground is a product named Claybord, which is available in art supply stores. Masonite or plywood are good substitutes for the traditional solid wood panel used in earlier times. When applying egg tempera, it is imperative that you work quickly. Egg tempera is extremely quick-drying. An effective technique for creating the planes of color and value is hatching and cross-hatching.