Airbrush or Spray gun?

Little confused at what I should use to spray my board. I just want to spray my board with two colors blending them in, but at the same time leaving enough bare areas to see the whiteness of the shaped board (towards the stringer of the board). In other words, I want the lateral aspects of the board sprayed throughly blending into another color and the center or close to the stringer, white with blotches of the spray. So, airbrush or spray gun? Thanks all.