Use about a cup of henna powder for short hair, 2 cups for shoulder length and 3 cups for super-long locks. Add enough lemon juice to the powder to create a paste that looks like pistachio cake frosting. Let the mix sit overnight so the dyes can release and give you more color.
Wash your hair, but don't dry it. Instead, comb it out as straight as you can, parting it straight down the middle. Wrap an old towel around your shoulders first and put on plastic gloves. Henna can kill a manicure or a set of cute pajamas with a single errant drip.
Bundle most of your hair on top of your head with a claw clip. Leave a 1/4 inch layer hanging down at the nape of your neck. Scoop up some henna frosting and spread it onto your hair from roots to ends just like peanut butter. Release a second layer of hair and continue, working your way to your hairline.
Swirl your hennaed hair into a bun on top of your head and tuck every strand under a shower cap. Pop in your favorite DVD and let the henna sit on your hair for about an hour. Indulge in some ice cream or answer your texts while you wait.
Rinse the henna out of your hair, combing it through to catch any dried powder. Your hair should be vibrant red to auburn. If your hair is already black, you'll see fiery red highlights.
Mix some indigo powder with water to make up another "frosting." The paste itself will look black, but watery runoff will be vibrant, dark blue. No worries; the combination of henna and indigo colors hair to look like black satin.
Section your hair as before, applying the indigo from the nape of your neck to your hairline. Since indigo doesn't need time to release, apply it right after you mix it. Bundle your hair back under the shower cap and finish your movie, letting the indigo sit for another hour.
Rinse the indigo paste out of your hair, which should be shiny, soft and as black as can be. Style as normal or let it air dry. Either way, make some dinner plans to show off your new 'do.
Always use body art-quality henna and indigo on your hair. Body art-quality products are pure plant extract and deliver intense color. Henna and indigo "made" for hair could give you the fading color and frizz you're trying to avoid.
Don't try to dye your hair with commercial dyes after using henna. You'll end up with a damaged, discolored head of hair.