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.
Hatching is the use of linear strokes laid closely to each other to create a value or color.
Cross-hatching occurs when the strokes overlap, creating darker values and deeper color.