There are several ways to sharpen your images. Some of these techniques re good and others not so much. I have found that using the unsharp mask filter is ok but can lead to an even more noisy image if overdone.
So after doing a little searching I found a technique that is called, High Pass sharpening and you use it like this:
1) Make a layer copy of the background layer and then make the background layer invisible. This way you can revert back to the original if a mistake is made.
2) Do all your editing of the picture. Make sure it's done to your satisfaction.
3) Make a layer copy of this layer.
4) Open filter>Other>High Pass. A dialog box will open. Move the slider to a number between 5 - 10 pixels (use your own judgment on this) and press ok.
5) The third layer will now be grey. Under the blending menu select overlay, soft light, or hard light.
Bam! Nice sharp image.
Let me know what you think.