Some people use natural methods to colour their hair, as they have found these methods to be chemical-free and sometimes easier and less expensive than commercial products. One natural method for home colouring uses vinegar and soy sauce as dye, which is suitable for dark hair and produces a brown tone with soft highlights.
Place an old towel around your neck and use gloves because the solution will stain.
Stir the vinegar and soy sauce together.
Comb the solution through hair, covering all hair thoroughly.
Leave on for at least 20 minutes.
Shampoo and style as usual.