Though you can have some of the body in a head shot, you need to keep it to a minimum (or it's no longer a head shot). Though his head is squared up in the shot, it too can be at an angle by twisting the camera. I guess that would be a 45/45/45.
The other consideration in shooting a head shot is to use a lower aperture to decrease your depth of field and blur out the background. It isn't a requisite but usually helps. You can see that was done in this shot. The aperture in this shot was 2.0 so that his whole face was in focus. Keep an eye on that in your magic preview screen - so that you get what you want.
POST: slight saturation of shirt; color adjust for skin tone and airbrushed blemishes on skin.