Set the brush as above and brush across the canvas until you have a similar look to the one below. Apply the filter > Distort > Ripple Effect with the standard settings repeat a further four times.
Apply the Filter > Blur > Radial Blur Zoom 50% click Edit > Fade Radial Blur > 75%. Set the eraser as above and brush lightly across the canvas until you have a similar look to the one below. Apply a Filter > Blur > Gaussian Blur.
Set the radius so you get the required detail of airbrushing Apply Edit > Transform > Distort to create the required shape depending on the blur applied it should come out something like below.