It's looking really good!
As I posted on FB, what I did on my first shield was to use stencils, by using the clear plastic stencil sheets you can get at craft/hobby stores. I printed out the charges on plain paper, put the plastic sheet over it, and cut out the stencil with an x-acto. Then I used spray-on stencil adhesive to attach it to the shield. It worked OK, but since I was using spray-paint, the paint still escaped under the edges of the stencil a bit, and I had to use the x-acto to scrape off the excess.
For my second shield, I used the first as a guide, but free-handed the outlines of the charges with a pencil, then painted to those lines by hand with a small brush.