For this tutorial I'm going to focus on fixing this gentleman's right eye. As you can see there is a tear that runs directly over his right eye. I'll try to repair the right eye by using the left eye.
First step - Create a selection around the left eye using the laso tool
The Select > Feather... command helps to soften the edges of the repair (which will make life easier down the road)
photoshopfeather selection dialog
Create a copy of the left eye and place it on its own layer using the New Layer Via Copy command (PC: Ctrl + J, Mac: Command + J)
Since the right eye needs to be a mirror image of the left eye use the Edit > Transform > Flip Horizontal command to mirror the copy of the left eye
Use the move tool to move the mirrored left eye into place. The repair looks pretty good, but the shadows around the nose look odd.
Use the eyedropper tool to select a shade of gray from the nose. Then select the paintbrush tool, changing its mode to Lighten with a fairly low opacity
With a couple strokes of the paintbrush, the shadows around the nose look a lot better and the eye repair is complete!