Open the picture-copy the layer-filter-noise-noise reduction; Filter-Blur-Gaussian Blur-Add Mask-Add Black-Set the foreground to white-Paint the skin with a brush-Stamp-Copy the stamp layer-Whiten (change the mode to "Filter Color") -OK.
One-minute quick whitening
Open the picture-create a new layer-fill it with white-change the mode to soft light-wipe off the background and hair with your skin when the foreground is white.