Henna has been used since antiquity in ancient Indian subcontinent to dye skin, hair and fingernail

If you are using henna powder, do as so. Mix 1/4 cup (60 ml) lemon juice or water with the henna powder using a whisk until you have a mixture that has the consistency of mashed potatoes. Cover the henna with plastic wrap. Allow the henna to rest for 24 hours at room temperature to draw the dye out of the henna.