Here’s an after-and-before shot I just took and airbrushed. It’s my first using the “blur and mask” method and took about ten minutes:

On the left I’ve plasticized my skin (should get better and more real-looking with practice). Click through for bigger.

Essentially what you do is duplicate the image onto a higher layer, distort it with blur and noise to remove blemishes but keep “character”, mask it all out, and then feather it back in with a lightly alpha’d brush.