Sometimes I like to give the skin in my photo's a little touch-up. Not too much, I don't want to have an airbrushed look, but enough to take away the obvious blemishes. To start, open your file.
In photoshop, get the Clone Stamp Tool (S). In the option bar, set your brush to the circle that has fading or feathering around it's edges. Pick a size that is large enough to cover the blemish, but not too large to start covering lots of detail.
While hovering over a good part of skin, hold the alt button and click. This will take that part of skin, and then when you click over the blemish will take the small piece you just took and put it there. It';s a bit like copy and paste. I zoom far in when I do my stamping, occasionally zooming out to check the overall look. When you are finished, it might look like this:
Check out the before and after: