Original picture:
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1. Open the picture you want to PS, select the "Zoom Tool" in the toolbox, and enlarge the eyes;
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2. Create a new layer;
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3. Select the color you like and use the brush tool
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, draw (as shown below) the eye shadow effect;
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4. Select Filter-Blur-Gaussian Blur;
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The blur radius is about 3.0 pixels;
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6. Set the eye shadow layer mode to "Soft Light" and the opacity to "70%".
Effect: