As far as lighting, I almost always shoot in the shade; these photos are no exception. Shooting in the shade gives softer lighting for portraits and a more even exposure between the skin, hair and clothing, allowing for more details to be captured. You still need to be aware of all of your light sources though. I look for lighting that sculpts and contours the face. You'll notice when looking at a lot of my photos how the highlights and shadows shape the face; the facial structure helps with this, but finding lighting that enhances it is key. If you are unsure of what I am talking about, go to youtube and search "makeup contouring"; the light that I like to use mimics the effect of good makeup contouring. I also enhance this light in photoshop by creating a new grey layer above a duplicate background layer, and set this layer to soft light mode, and check the little box that says "fill with 50% neutral color grey" in the new layer dialogue box. On this layer I use the dodge tool at 8% exposure set to the "midtones" range, and only slightly dodge the midtones of the skin (these are the tones between the highlights and the shadows). This creates a softer lighting effect. Then on the same layer I set the dodge tool to effect the "highlights" range at 8% exposure, and begin dodging only the highlights of the skin. This is how I achieve that soft glowing look on the skin. While still using the dodge tool set to the highlights range, zoom in on the eyes and dodge the highlghts in the iris of the eyes in order to bring out the color and detail in the eyes, and also dodge the catchlights just a little bit if they are present. You have to be very careful with this, otherwise it becomes obvious that it's been edited. On the same layer, switch to the burn tool, set to 6% exposure and set it to effect the "shadows" range. Then burn the shadows on the cheek created by the cheekbone (this shadow goes from the bottom of the ear to just halfway to the lip) in order to enhance the contour. Again, I really encourage anyone who attempts using this technique to become familiar with how to contour a person's face using makeup. Watch tutorials. Doing this will make adding these highlights and shadows much easier because you will have an understanding of exactly why you are doing so. Next, I use a curves adjustment layer for contrast and some tonal adjustments, a selective color adjustment layer to mess with each of the color channels (I highly recommend experimenting with this one, because this is how I achieve my dramatic color changes), and a hue/saturation adjustment layer to tone down the color vibrancy. Make sure that the hue/saturation layer is positioned underneath the rest of the adjustment layers, and above the layer used to add highlights and shadows to the facial contour. If you don't know how to use or find adjustment layers, a quick search for a youtube tutorial will have the answers for you.
Since all of these adjustments are done on separate layers they become non-destructive to the original background layer. It lso means that you can adjust the opacity of each of these layers, giving you control of just how much they affect the image.