Photoshop to vector
Airbushing Tips & Tricks 2 in Photoshop
by - Tremorwave

Set a pen tool as above and scribble across the canvas until you have a similar lock to the one below.

Apply the Filter --> Distort --> Wave effect with the standard settings. Then Edit --> Fade Wave. Repeat this another two times but don't fade the wave on the last round it should look something like this.

Apply the Filter --> Blur --> Radical Blur Zoom 50%
Click Edit --> Fade Radical Blur --> 75%.

Set the eraser as above and brush lightly across the canvas until you have a smilar look to the one below

Apply a Filter --> Blur --> Gaussian Blur set the radius so you get the required detail of airbushing Apply --> edit --> Transform --> Distort to create the required shape.

Here's an example of use

PS: Tutorial written with the permission of the Author!