Dip top half of hard-cooked egg in 1 color and the bottom half in another. Or, dip each half of the egg in the dye for different lengths of time, creating different shades of the same color. Mix 20 drops food color and 1/2 teaspoon vinegar in small container. Paint hard-cooked eggs with a small paintbrush or cotton swab. Go wild with stripes, polka dots and zigzags. Before dyeing, place rubber bands, stickers such as chicks, rabbits, flowers or other springtime favorites, or paper reinforcements on the eggs to create the design of choice. Once dry, remove the rubber bands, etc., to view the design. Write initials, names or draw pictures on the egg with a white or light colored crayon before dyeing. Mix 1/4 cup boiling water, 1 teaspoon vinegar, 1/8 teaspoon oil and 4 to 8 drops food color in shallow bowl. Gently roll egg in the mixture for 30 seconds, or until the egg is the desired shade. Transfer the egg to a second color mixture, and repeat the process. Allow the egg to dry completely. Wipe away excess oil with a paper towel. Place several eggs in a colander in the kitchen sink. Splash eggs with vinegar. Drop yellow food color onto eggs. Gently shake the colander for a few seconds to help the color spread. Let stand 30 seconds. Repeat with 1 or 2 additional food colors. After the final stand time, lightly rinse eggs with water. Drain completely. Allow eggs to dry.