If you haven't already hard-boiled your eggs, place them in a large pot with water. All the eggs to reach a boiling point and set a timer for about 12 minutes. Remove them from heat and allow them to cool.
Be sure and allow eggs to cool before coloring. They should be at least room temperature before coloring.
In a cup combine 1 cup water and 1 tablespoon distilled vinegar. Add food coloring and mix. Add more food coloring if needed and mix until you get the desired color.
Next, color eggs just like you would with store-bought coloring.
Have fun decorating.