An important thing to remember when retouching photos is to exercise a little restraint because you don't want the end result to not resemble the person at all.
Open the photo you want to use for this exercise. I will be using the photo below:
Duplicate the background layer by either pressing Ctrl + J or selecting Layer > Duplicate Background Layer.
You should now have two layers that show the same photo. Make sure you are on the top layer, it will appear blue in the layers palette, and choose Filter > Blur > Guassian Blur.
Adjust the Radius slider until you get a pretty good blur going on. Make sure you set the blur level so you don't see the freckles. Don't worry if you start to lose detail; we'll fix that in a minute.
With the blurry layer selected, click the half black/half white circle at the top of the Layers Palette and choose Levels.
Click OK to close the Levels dialog box. Click and drag the adjustment layer so that it's between the background and blurry layers in your Layers Palette.
With the blurry layer selected (it'll be light blue in the Layers Palette), choose Layers > Group with Previous. This groups the blurry layer with the adjustment layer, enabling us to use the layer mask.
Select the Brush Tool , and from the options bar at the top of your screen, make sure you have a soft brush selected and adjust the size according to your photo.
Now we need to set the foreground color to black and the background color to white, making sure that black is on the top.. Click the layer mask to select it (a tiny hairline border will appear around it),
then paint out the areas that do not contain freckles. In this activity we will paint out everything but the cheeks and part of the nose. Here is my finished photo.