Step 1: Sketch an outline layer of the design desired.
Step 2: Paint the basic color of the car with airbrush tool.
Step 3: By using airbrush tools, render the dark area where the shadow is beneath the lighting source.
Step 4: Paint the basic black color for the windshield, headlamp and intake blackout.
Step 5: By choosing the lighting source on the top, render a soft shade of white on the hood, roof, pillar and wheel arch.
Step 6: Using different layer, highlight the hardest point of the lighting by overlay the white airbrush on top of the first layer of the previous lighting shade.
Step 7: Add up a bit shadow by airbrushing the lower part which doesn't expose to the lighting source.
Step 8: Create a white stroke path to create realistic depth of parting lines.
Step 9: Finally, add some details of the front headlamp, garnish and fins ventilation according to desired design.