Youthfull Looking Skin

Open up your photo, select the pen tool and draw around the whole face area, excluding vital features like eyes and mouth also don't get to close to the hair line.

Copy & paste your selection to a new layer, then goto "filter > blue > gaussian blur" blur the layer by about 2 pixels if it looks over blurred then take it down to about 1 or 1.5.

Add a layer mask to your layer.

Select a reasonable brush size and the color black. Start to brush over things like the eyebrows, little bit of the hair line, nose holes, around the lips etc…, basically just vital features that make the face, I've also brushed over some facial lines. Here's mines.

Now the before and after.