Pour 10-20 drops of liquid food coloring into the bag of rice, along with up to ⅛ teaspoon of white vinegar (optional). Seal the bag and shake the rice around the spread out the food coloring more evenly.
Place an egg in the bag, seal it up again and gently shake the bag around until the egg is fully covered with food coloring.
Unseal the bag, carefully remove the egg (wearing gloves if desired to prevent the food coloring from staining skin) and place it on a plate to dry.
Repeat the previous steps with as many colors and eggs as you wish. If reusing the same bag of rice to dye multiple eggs, add a few more drops of coloring in between eggs to keep the color vibrant.
Notes
Rice dyed eggs are safe to eat and can be used to make dishes like devilled eggs.