Cover your work area with a plastic tablecloth to protect it from any spills or stains.
Boil 4 cups of water or ½-¾ cups of water per color. If you use more than 6 colors, you will need to boil more water.
Add 1 tablespoon of white vinegar and ½-¾ cups of water to 6 cups. (For small mason jam jars you will need only ½ cup, but coffee mugs will use about ¾ cup of water.) Add 25 drops of food coloring to each cup. Mix it together.
Use a small spoon or wire egg holder to dip the hard-boiled eggs into the cups of dye for 3-5 minutes (or longer for more vibrant eggs).
Remove the eggs from the dye and allow them to dry.
Store the dyed eggs in the refrigerator for up to 7 days from when they were first hard-boiled.
Notes
Tips:
Depending on the size of the cup, you may need ½-¾ cup of water per color.
Add less for coloring for lighter, pastel colors. Add more food coloring for darker colors.
Allow the egg to sit in the dye longer for a more vibrant colored egg.
Use pint mason jars or coffee mugs instead of bowls. Bowls are wide, so the water won't cover the entire egg.
Hot water allows the dye to mix and absorb better than cool water.
Keep the egg carton to store the finished eggs. Spoons, slotted spoons, tongs, and wire whisks can all be used to transfer the eggs in and out of the dye bath.