Wayne,
I don't have a pictorial of the process, but it isn't too difficult.
When I create a multi layer mask, I add alignment marks to each mask. I also create the mask as overlays so that each layer is aligned and the alignment marks, or targets, will be exactly overlayed. For a Stars and Bars, I make the bottom layer the overall outline, which will be painted white. The next layer goes on top of the existing mask and covers the white outline so that the internal star doesn't get painted over. Then the blue gets sprayed. Then if it's a post '43 insignia, the second layer gets removed and the next layer for the red gets placed.
The alignment marks make it easy to place one layer over the other.
That's how I do it.
Regards,
Stan