When dealing with skin smoothing in Photoshop it is difficult to find that balance between skin that appears naturally smooth and blemish free and skin that appears unnaturally glossy and fake. This technique I came across while researching techniques for editing photos of bikini models for Hot Bod Bikini Calendar. So far it’s my favorite skin smoothing technique.
Duplicate your background layer
On the duplicated layer add a surface blur
Filter > Blur > Surface Blur
There is no magical formula for this. Play around with the settings until you’re happy. You want to have a nice softness to the skin without losing the detail around the eyes, nose, and mouth.
Create a NEW layer
Go to Edit > Fill and fill your new layer with 50% Gray
Filter > Noise > Add Noise
Set it to 3%
Filter > Blur > Gaussian Blur
Set to 1 pixel
Set your Gray filled layer to Hard Light
Layer Style > Blending Options > General Blending > Blend Mode: Hard Light
Create a Group and put your Gray filled Layer and your Duplicated Background Layer in it.
Add a Layer Mask to your group and fill it with Black
While on your layer mask, select your paintbrush tool and choose an appropriate size brush. Select white as your foreground color.
Now you can start painting the areas of skin you want to smooth out. Be careful not to smooth over detail areas around the nose mouth and eyes.
Finished Product When you're done you should have a natural looking skin texture that doesn't look too glossy or fake.