What's the best method for skin smoothing that retains some detail? I hate the gausian blurred look that most people use.
You need to select the skin you want to blur. Whether it be my pen tool, or any method. The easier way to select skin is to go into Photoshop > Select > Color Range
Then select the eyedrop that has a + sign to it. Click the surface on the skin that you would like to smooth. Keep in mind that skin might have different tones, so click on all the ranges of tones until you have selected the entire skin surface. If you select other things, that's ok.
Click ok, and you will have a selection of the color ranges you selected. Make the other layers invisible to just see the skin selection. Erase anything that you don't want blurred with a soft brush.
Once you finish, click on the layer with the skin selection and duplicate it. Make the layer you just duplicated invisible. And the bottom layers that are invisible, visible.
Working on the first skin layer go into filters> blur> surface blur.
Select a good amount. This step will vary depending on the quality of the image.
By now, your picture should look like crap. This is good. Finally make the top skin layer visible. On that layer go to filter>other>high pass and again select a good amount.
Change that layers blend properties to soft light. Then adjust the surface blur and high pass layers until you get a good balance.
The above was taking into consideration you have intermediate knowledge at the least in PS. If you don't, ask more questions in what step you're having difficulty with and I will expand.