Updated: Jan 15, 2020
A few people have asked me how to use Henna so I thought I would write this up. Also, I just did this to my hair so.. I might as well write up how I do it. I have done it many times, in different ways, and this is the best of my trial-and-error ideas....
Things you'll need:
Henna (2 100g boxes)
Essential oils (Your choice, I recommend Rosemary oil)
Cheap conditioner (Think Suave or something similar)
Vaseline or beeswax salve (healthier option)
Old plastic mixing bowl
Old plastic mixing spoon or spatula
Lots of saran wrap
At least two pairs of latex gloves
Old towels (At least two, one to wrap around your neck, one to lay on a pillow if you sleep while this is in)
Old shower cap
Freezer bag (For storing leftover henna)
Free time (8 hours if you are leaving it on while sleeping, which I recommend)
Most of these items you probably have hanging around the house somewhere.. just take a look around.
First of all, you need to get the Henna.
I recommend Body Art Quality (BAQ) henna as it stains more red and probably stays in longer. You can also get regular henna but it stains lighter and will probably require more reapplications of henna, which isn't a bad thing as it strengthens your hair the more you put it on. It actually bonds with your hair follicle, adding more strength than what was there previously. If you want to get a different color of henna, the only other color I can recommend is black henna, which has indigo dye in it. The only brand of that I can recommend is Ancient Sunrise from http://www.mehandi.com/ as a lot of black henna contains extra products that are not safe and no true indigo in the dye. I have tried light brown henna but it did not work well at all and faded extremely quickly as well as leaving little color, so I would not recommend trying it.
I recommend Jamila BAQ or Red Raj henna. I have tried several types and these seem to be the best for the cheapest amount of money. I personally get them from http://myworld.ebay.com/herbalbeautysupply and have had no issues, and they have cheap or free shipping as well. You can also buy henna from http://www.hennasooq.com/ or from http://www.mehandi.com/ however mehandi seems to have more expensive shipping. They do have a lot of good tips for applying henna though, so their site is worth checking out. I don't recommend buying from an Indian or Arabic grocer as you have no idea how long the henna has been sitting out, and the older and longer henna sits, the less capable it is of dyeing your hair, & it's often not BAQ henna when you find it in a store. You can also experiment with different henna mixtures. http://www.hennasooq.com and http://www.mehendi.com have different henna mixture recipes available for different shades of red.
Good example of henna on what is probably blonde hair
I mix the henna (2 packs of 100g since I have shorter than shoulder length hair) with lemon juice that I get from Aldi or Sam's Club, and hot water, at a mixture of half and half You can also get it cheap locally at Price Chopper, in the juice section. Lemon juice helps to release the dyes from the plant quicker. I mix it in a plastic bowl that I don't really care much about. You don't want to mix it in a metal bowl as it will take on a greenish cast rather than red on your head. I use an old plastic mixing spoon to mix it well, until there are no more chunks and it is about the consistency of yogurt. I then add in essential oils. I recommend adding Rosemary because it is also good for the scalp and hair, and it's not a very greasy oil but will help if the henna dries your hair and scalp out a bit.
I leave the henna to sit for a full 8 hours. I recommend putting it in a warmer place, away from light or windows, and covering the bowl with saran wrap and letting it sit overnight. When it's done, normally it takes on kind of a brownish-green tint.
Before putting the henna on, wash your hair with a detoxifying shampoo, and then dry it. I recommend Aphogee Shampoo for Damaged Hair, or something similar, maybe Rusk Clarifying shampoo, since it's totally sulfate-free. Don't apply conditioner, as this will make it harder for the henna to bond with your hair.
You will want to prepare your bathroom for the application. Put saran wrap or trash bags over your counters and sink, and trash bags on the floor. Get your old towl out and wear an old shirt that you don't care about staining. Wrap the towel around your shoulders and secure it with a clothespin or rubber bands. Put vaseline or beeswax cream (healthier option) over most of your face and hairline. This stuff will drip, so that's why I recommend putting it over a lot of your forehead and cheeks. Get your saran wrap ready by pulling some out and cutting a long strip as you'll be putting it around your head. Put on your plastic gloves and move the mixture into a plastic baggy. I tape my plastic baggy to the sink and pour the mix in slowly. Be careful as you are preparing the henna, as you don't want to get the mix all over, and it is very messy so a mess can and will happen if you aren't careful. When you are in the bathroom, cut a small hole in the bottom of the bag when you have it over your head. Mix in the henna, starting at the roots and working in well, and then working out to the ends. I recommend piling it on top of your head as you're working it through. You will see shortly why I asked you to plastic wrap your bathroom and trash bag it too, because this stuff gets all over. Take off your messy gloves and get your saran wrap out. Wrap it around your head, paying close attention to the areas around your forehead as you don't want to get a lot of dripping going on. After your whole head is wrapped, apply the shower cap. If you want, you can even saran wrap the shower cap for added help in keeping the dye in.
I recommend leaving it in 8 hours, if you can, but you can leave it in as little as 4 hours and see some results. If you need to cover grey or have lighter hair, try to leave it in the full 8 hours if you can. The longer you leave it in, the better a chance you give the henna to bond to your hair and make a brighter red. Make sure to take it easy while you have it in your hair and lay back if you can, as it drips more if you aren't laying back, or completely laying down. Take it easy. If you sleep while this is in, put down a trash bag over your pillow, and then an old towel over the trash bag. Try to sleep on your back if you can and try not to move too much. (Easier said than done.)