For a long time now I've been wanting to make my own henna. My only problem had been that I had no clue where to obtain the henna powder. Today I found out that henna powder is easily found in any Indian grocery store, and that there is one just down the street from me.
I mixed the henna per various internet recipes: some highly concentrated tea (boil tea bags with water), some lemon juice. I added some wine for fun. It ends up looking like Indian food, I think.
Use a plastic spoon to avoid unwanted oxidation.
I cut a rough mask out of a sticker which helped me lay down most of the design, but it didn't stick. In the future I will find super-sticky sticker paper and cut the designs out with a laser cutter. Because my I was doing this rather hurriedly, I picked my leg as the most hassle-free spot I could find for a henna tattoo.
I only let the dye sit for 2 hours (instead of at least 24) and took the dye my skin after only a few hours. This might account for the reddish color, though it might also be that I am using a henna targeted for use in hair. If I can't get a brown color by using better technique, I will invest in some Jamila henna, which really isn't that much more expensive (but I will have to buy it online because they do not stock it at the store here).
And yes that is an ouroboros similar to the kind seen on the homonculi in Fullmetal Alchemist.
Other thoughts: henna smells really good! It reminds me of green tea ice cream (or vice versa?). Even now my leg smells like it.
Other other thoughts: The henna is $3 for 200 grams, and it isn't terrible stuff. I used ~50 grams and made more than enough (it will go bad before I get anywhere near finishing it, even though I plan to make some awesome tattoos on my friends in the next few days if they let me). Conclusion: fun and inexpensive art form - I like.
The henna turns a brown color within a few days (instead of remaining a reddish color). Most people prefer or expect a brown color from the henna, so this is good.
I didn't get to use the laser cutter but I did develop a substitute system for making nice masks. I cut adhesive PVC sheets into standard letter paper size, print out designs, and use an exacto knife to cut them out. The results are nice.
Here's a photo of Angie's Naruto symbol thing, right after the henna was applied:
Since I didn't leave my henna on overnight, it is starting to fade already, which is good because I want to wait for it to disappear before I do another one.