Gently place eggs in single layer in large saucepan. Add enough cold water to cover eggs by 1 inch. Cover. Bring just to boil on high heat. Remove from heat. Let stand 12 minutes. (Adjust time up or down by 3 minutes for each size larger or smaller).
Pour off hot water and rapidly cool eggs by running them under cold water (or place in ice water) until completely cooled. Place small dot stickers all over eggs. Or, use a white or light colored crayon to draw polka dots on eggs.
Mix 1/2 cup boiling water, 1 teaspoon vinegar and 10 to 20 drops food color in a cup to achieve desired colors. Repeat for each color. Dip hard-cooked eggs in dye for about 5 minutes. Use a slotted spoon, wire egg holder or tongs to add and remove eggs from dye. Allow eggs to dry. Remove stickers, if using.