How do you mask the aircraft to spray such an intricate grid of lines?
The picture looks freehand to me. Since you are going to cover it with another coat, i don’t think you have to worry too much about overspray.
That pic shows an aircraft that has been both post-shaded, and pre-shaded.
Looks like the plane was given a dark base coat and the centre of each panel has been sprayed with white, then an overall thin white coat added last of all