Any idea how raybot paints?

[Purity]

One thing that has always puzzled me is how in he world raybot paints so incredibly smooth and realistically. I'm a huge fan of his, and aspire to paint like him some day. So does anyone know how he paints? Does he use airbrush? Brush stroke? Spray paint? What?

[Green Skin]

I'm pretty sure he uses an airbrush. Best way to find out though is contact him directly.