I have been using this effect lately for some of my portrait photos and thought of sharing one of the methods I use to improve those kinds of photos. I mainly want to focus on the eyes, but I'll go over some other extra quality touches as well. So let's start, uh?

1. First let's start by bringing up a portrait style photo into Photoshop. It can be obviously anyone, but try to get a photo that its main focus are the eyes. For this tutorial I will be using a photo of my little brother as an example. (If you wish to use this photo as well, please contact me and I'll send it to you). Now, if your photo is bigger than 2000 pixels in width, you might want to reduce it to max 1500 pixels for better control. Reducing the image size most of the time improves quality as well. (After we are done with everything, you can reduce the picture even a bit more to get the best quality).

2. The first thing I'll do to the photo is improve colors, contrast, brightness, etc. You will need some general knowledge of Photoshop in order to do this. But just in case you are having some difficulties, I'll explain (Briefly!).

Get in Image > Adjust > Variations:
This opens a window with variations of colors you can combine/mix until you get your desired outcome. There are lighter and darker variations on the right, colors on the left, and up top there is original and you edited version; to start over simply click on the original thumbnail.

Get in Image > Match Color:
In the window, the two basic things you might be using as for now are the Luminance and the Color Intensity. The luminance basically lights up the image while color intensity increases or decreases the color pressure in your image.

Get in Image > Adjustments > Auto Contrast/Level/Color:
This might be very useful for lazy people. This will automatically do the job for you. But it's not very flexible and you might not learn anything from it.

Now that I showed you of the few tools of Photoshop for photo manipulations, take your time and bring up the best quality you can. But be careful, don't exaggerate, people tend to do that, and it makes the photo look unnatural. We don't want that do we?

3. I'll start by cleaning a bit the skin to make it smoother using the Spot Healing Brush. All you need to do is grab the Spot Healing Brush and click and/or hold on the places you want disappeared, such as black dots, scratches, or anything else that "destroys" the skin. Make sure you change the size of the brush depending on the area that you want off.

4. Next, we will improve the skin a bit more by first opening the channel palette if it isn't already open (you might even find it in a tab of your layer palette) You do that that by getting into Window > Channels. Click on the little dotted circle icon at the bottom of the channels window ("Load channel as Selection"), which will select all the highlights of the current photo. Go back into your layer palette while the selection is still on, make a new layer above the photo layer and fill it with white. Deselect (CTRL+d). While the highlight layer is selected in your layer palette, go into Filter > Blur > Gaussian Blur. How much blur to apply? Come on, I can't explain you everything, that's up to you. Try choosing the best choice until you see the "smoothness" effect on the skin. Just in case you really want to know how much blur I applied, it's about 3.0. From here you can play around with this layer so it will best fit the skin in your photo. Those "playing" can be lowering the opacity of your layer, erasing some parts that look awkward, putting the layer on blending options such as maybe soft light, but all those options are 100% up to you and to the photo you are using. As you may notice, this smoothen up the skin and makes the photo have a much better quality.

5. I think that's enough for the general retouch. A little tip: if you got a portrait photo with background showing more than about 30%, you may use the Blurring tool to blur out the background and bring out the face a bit more. That is a very famous effect you might want to use more often.

The eyes:

6. So we reached the main part. Let's start by zooming in to one eye.

7. Grab the elliptical marquee tool, and try making a perfect circle that would best fit the eye. If the eye is a bit closed, it would of course not make a perfect circle, then use the selection options above such as adding and erasing, and try to get the whole selection fit the eye.

8. While holding on the selection and making sure the layer selected on the layer palette is the photo, go into Layer > Feature and give it about 5-10 pixels.

9. After that happens the magic, you go into Image > Adjustments > Brightness/Contrast. In that little window, move the contrast slide to the right but not too much. You can see a preview of the photo behind and I am sure you will make it the best amount. Remember, try to keep it real. You can play a bit with the brightness slide as well if you wish.

9. Great! Now do the same for the other eye.

10. Well, it wasn't very hard, was it? I hope you learned quite a few methods on how to improve quality of a portrait photos. Here is my final outcome with some effects (black and white)

Thanks for reading ;)