Here is a photo with the henna paste still on the skin. I never use "black" henna, as there is no such thing! I use pure, safe, all natural Jamila henna powder for all my work this year.
For this design, you may be able to see that I experiemented with two shading techniques. One was to treat the henna cone not unlike a pencil, using it to do shading motions with the paste.
The other effort, which may or may not result in an effective shade this time, was to mix henna paste with lemon juice & sugar to create a "wash". I used this diluted henna to fill in some of the flower petals.
I will let you know how this turns out. Click the photo for a close-up.