I've been working a bit larger than usual for me, using 10.5 x 10.5 inch paper. I decided to do another mandala based on those I saw on Pat Howard's Painted Prism blog. The problem with this size, of course, is that I can't scan most of the paintings and have to take a photo instead.
It isn't entirely clear on Pat's blog what is being done with the mandalas, but I think it's easy enough to decide for yourself what to do. In this case, I chose three colors (Permanent Yellow Deep, Permanent Red Deep, Prussian Blue) from my Mijello Mission gold palette, and mixed to get secondary orange, green and violet. I chose colors that I felt were close in temperature (warm-yellow biased or cold-blue biased) and that I felt would mix clear bright colors, which I think they did. That the reason for mandalas like this. You can see exactly how well the colors mix.
I painted with lots of pigment in the center to get the deepest value, then lifted color from the center, to see how staining each was. Each section, I negative painted around the petals with moderate value, and I blotted in a few places to get a range of values. The petals were painted with the complementary color (the color across from it on the wheel), trying to keep the values as light as possible. Then I used the complementary color to shade. In essence, this shading becomes a mix of ALL the colors on the wheel and an example of how muddy the colors might get. Not very muddy!
I highly recommend visiting the Painted Prism blog. Pat doesn't have a tutorial for these mandalas, but she has many other free tutorials you can read online for free, or buy as a PDF for a good price. Her work is beautiful, her tutorials excellent, and it's just a great resource.