1. Get 100 grams of good, skin-quality, totally sifted henna powder, a bottle of lemon juice, honey, and 10ml of essential oil high in monoterpene alcohols such as lavender, tea tree, cajeput, ravensara, rosemary, clove bud, or eucalyptus. You will also need a sealable bowl, and a spoon.
2. Put the henna powder in the bowl and add two or so tablespoons of honey.
3. Shake the bottle of lemon juice and beging stirring it into your henna. You want it to get all the henna damp to a mashed-potato consistency.
4. Seal the bowl and place somewhere warm.
5. After a couple hours, check the bowl. If the top of the henna has browned like an apple left out in the air, or if you see little brown puddles, it's ready to use. If not, seal it again and check back later. Every henna takes a different amount of time to develop color, from under an hour to over twelve. Be patient and it will happen.
6. Dump in your essential oil and stir until it's all mixed in. The henna may ball up like bread dough and refuse to cooperate. Keep stirring and it will eventually relax.
7. Add lemon juice a splash at a time until you get a consistency somewhere between yogurt and toothpaste. If you have lumps, you may continue stirring, or strain them out.
8. Add several drops of essential oils. This will help smooth the paste out and help more dye come out.
9. Lavender is good for sensitive skin, while clove bud should only be used on those that aren't sensitive. The best oils are tea tree, ravensara, and cajeput. You can add other oils just for the scent, as long as they are skin safe. Citrus oils are phototoxic and should not be used.
10. If you're going to freeze the henna for later use, do it now. Otherwise, put it in your applicators.
11. Wait. Most henna is at its peak a day or more after the final mixing.
Apply! Make sure the henna is all touching the skin over hairs, and that all larger areas are fully filled in.
Leave on the skin for as long as possible, keeping the area as warm as possible.
The henna will fall off on its own. Keep it out of water for as long as possible to allow it to darken. Lotion helps remove the henna. The starting color will be pumpkin orange and will darken over the next day or two to its final color.
Seal your henna with sugar/lemon or hairspray before it falls off, as most henna designs need to stay on the skin 4-8 hours. You can wrap the design in tissue or paper tape to hold heat in. If you're cold-natured or in a cold place, wrap your henna in toilet paper, then saran wrap and leave it overnight.
TipsBefore the henna is totally dry, but after it stops looking shiny, apply a mixture of lemon juice and sugar with a cotton ball. This helps the henna stay moist, and keep it stuck to the skin. Heat equal parts sugar and lemon juice until the sugar melts and you have syrup.
If you aren't sure how to pick a good powder, see the listing on How to Choose a Henna Powder.
Add less honey if you're in a humid area, but don't add too much more or it will dry too slowly. You can also use white or brown sugar, melted candy, pure sucrose, dextrose, or fructose.
You can try different liquids to make your mix. As long as it's acidic and skin safe feel free to try it. Tea, juice, clove buds, rosemary, dried limes, red wine, vinegar, coffee beans, and tamarind are all common ingredients in henna mixes.
Warmth will make the henna develop color faster and cold will slow the process down.
See How to Care for a Henna Design for more on aftercare.
WarningsDo not use metal bowls or spoons, as the henna can react with the metal and tarnish.
Henna is a stain! Use latex gloves to protect your hands, an apron for your clothes, clean up any stray henna ASAP; basically do not allow the henna, even after applied, to come in contact with anything porous that you don't want stained. Bleach will remove henna from most bathroom/sink fixtures.
Beware of any henna that claims it is "black" - these products often contain chemicals that are harmful, can cause allergic reactions and lead to scarring