Paper - Secure one blank card to a flat painting surface with removable painter's tape.
2. Paints - Prepare each color in a separate well on a palette using only a small amount of the paint (about the size of a little fingertip). Moisten the paint with water and mix with a brush to an inky consistency. Clean the brush well before mixing the next color. After the paints are ready, refill the water container with clean water.
3. Using a clean half-inch flat brush, dip it into the clean water. Holding the wet brush perpendicular to the paper, "draw" the tree design onto the paper. Start at the top of the tree and work downwards in a zig-zag motion, leaving a few gaps between lines.
4. As soon as the water drawing is in place, dip the brush into one of the pre-mixed colors and then gently tap the brush at various spots on the wet tree design. The paint will immediately start to run along the water design. Quickly rinse the brush and dip it into another color. Again, tap the brush onto the wet tree design. Repeat the process with the selected colors. To assist the blending, gently tip the card in different directions.
5. Spattering. When the tree painting has dried, dip the bristles of a discarded toothbrush into one of the paints. With the bristles facing the paper, scrape the bristles with a finger or small object. Allow to dry.
6. Experiment with different color combinations and tree patterns with the rest of the blank cards.