Retouching Area Blemishes

If your image contains areas that are blemished, and particularly if they are oddly shaped or diffused in nature, the Patch tool is your best bet. In the following example, the mud splotches above and below the lips are good candidates for retouching with the Patch tool. There are a couple of ways to use the Patch tool, but here is the method that I think is the most logical:
1. Zoom in on the muddy upper lip.
2. Select the Patch tool by pressing J. Notice its options appear in the Options palette.
3. Click the Destination radio button in the Options palette.
4. Just as you would with the Lasso tool, draw a selection around the area that you would like to use as a clone source. Pay attention to the shape of the destination area to which you will drag this Patch selection and try to match the shape or at least an edge shape to that of the destination area. You can use the Shift and Option/Alt keys to add or subtract from your Patch tool selection area, just as you can with a Lasso tool selection. Depending on the image you are working with, smaller Patch selections may work better than larger ones, especially when working with detailed images.
5. With the Patch tool still active, click anywhere inside the selected area (the marching ants) and drag over the area you would like to patch.
6. Repeat the preceding steps as many times as it takes to patch the areas you like. Photoshop blends the patched area for you, eliminating the need for feathering the selection.
When you have completed all your retouching enhancements, you can follow up with some finishing touches such as sharpening to prepare your image for print.