I'm posting this here so it doesn't get lost.
Consider yourself hooked lol. Here, free how to buy, sift, mix, terps, order form with a lot of extra goodies you can order for cheap to try out.
http://www.hennapage.com/henna/what/freebooks/mix.pdf
How to apply and seal. Make sure to watch the cone rolling video. I started off with a jac bottle but if you want to do anything other then playing occassionally, learn to roll and use cones. They are sooo much easier on your hands.
http://www.hennapage.com/henna/what/...howtoapply.pdf
Here is a henna 101 that I wrote up for another forum to get you started.
Henna 101
It starts with a henna plant. Dry and powderize the leaves into a finely strained powder (or buy it that way from a certified dealer). Mix it up: There is no one way to mix it and no set recepie to use as it all depends on too many variable such as freshness of the henna powder, that particular crop, was there drought that year? climate where you are, skin alkalinity, your health in general, what you use to mix with, what you mix in at what stage of the process etc.
Normally I mix it with freshly squeezed and strained lemon juice. I strain it through a coffee filter as there can be no particles in it that wont fit through my point. I let it sit covered in my boiler/laundry room for 12 hours where it is nice and warm. You have to wait for the lemon juice to make the stain release. Then you add "terps", a monoterpene essential oil. I normally use lavendar as it is safest for pregnant women though this time I used a mixture of Naoli, Wild Thyme, and Rosemary oils. I normally add about 10 drops to a bowl full of paste. Let that sit for about 6 hours. Then I add honey. The honey is to keep the paste from cracking as it dries on your skin. Our climate is very dry. I've also used fructose, dextrose, and plain old table sugar to make the paste stringy to get fine lines. The honey works best though to keep the paste flexible.
Using triangles cut from mylar, I roll cones with various sized tips. You can see what they look like here:
http://www.mehandi.com/shop/mylarcones/
I put the henna into a ziplock bag and seal it. Cut off the corner and stick it way down into the cone and squeeze enough out to fill the cone. Tape up the cone, put the baggie in another ziplock, seal, throw in the freezer. It has to be kept frozen or it will expire, not stain well.
When I am ready to do a design I thaw it out and warm it to room temprature. Then I squeeze out the paste to make the design I want. Check out the link above if you haven't yet.
I let the paste dry and sit for as long as possible. I normally use medical tape and tape it all up then keep it on overnight. But this last time I just steamed my hand every 15-20 minutes for a couple of hours and got a great stain!
It works best on the palms and soles even though these areas get the most use. They have the most layers of skin to stain. So a good stain will last 3 or even 4 week. After paste removal, the stain will continue to get darker over the next day or two. Here is a picture I took. When I first removed the paste it was bright orange, then it darkened to a burnt orange. By the next it will "probably" darken to a light coffee color.
So, does that answer most of your questions?