I came across a good tip for airbrushing your own nails using a stencil........if you get one of those handy helpers (a small metal thing with arms and a magnifying glass, which stands up)and put the stencil between the two arms, you are then free to put your finger(s) under the stencil and use the other hand to airbrush. I haven't had chance to try it for myself yet, but it's worth a go I think.
Martine