This tutorial is about the process I go through when retouching a head shot.

(1) Here is Carly. The image has been color corrected in LR, but not yet retouched:

(2) The first step is to identify blemishes. My policy is to zap blemishes (acne, cuts and scrapes) 100%.  I do not normally retouch permanent features such as moles. In this case, Carly doesn't have any blemishes, but I'm going to make an exception for this tutorial and zap any skin imperfections I see, even permanent ones.  I've circled them in red.

(3)  To zap blemishes, I normally use the patch tool. Just make a selection around the area you want to correct, then drag the selection to a clean patch of skin that you want to use for your sample. Here is the image after using the patch tool:

(4) Next, I take care of any dark circles under the eyes or any wrinkles I want to diminish. First, copy the layer. Then use the patch tool to make a selection around the area you want to correct and drag it to the area you want to sample from. It's important to do this on a separate layer because then you can lower the opacity. Never remove a wrinkle at 100% opacity. That gives an artificial, barbie-doll look. I usually remove wrinkles at around 60% opacity. That keeps it real. Your subject will still look like themselves, only well rested!

(5) Here is the image after using the patch tool under the eyes and around the mouth:

(6) Next I spend some time on the eyes. First, I duplicate the main layer. Next, I select the dodge tool and make a couple passes over the whites of the eyes and also the iris. Then I adjust the opacity of the adjustment layer to taste and flatten the image. If there were visible veins in the eyes, at this point I would also clone them out using the clone tool. I've seen way too many photographers do such intense eye work that their subjects look like aliens. Don't overdo it!

(7) I wanted to give Carly a little bit more lipstick, so I just used the brush tool, selected a red color and painted over her lips with a soft-edged brush, then adjusted opacity to taste. Again, you'll need to first duplicate the layer in order to have the ability to control the opacity:

(8) Lastly, I run my "skin smoother" action, then paint back over the parts I want sharp with a black brush. Always keep the eyes, eyebrows, lips and hair sharp.

And here's the "before" image: