Hi Garret!!
Congrats for your new camera... and lens!!! 5dmkIII + 70-200 2.8 IS II its a killer combo, however let me give you some advices that helped me when I started taking pics
- Some guys already tell you about the post, but that its a personal taste, so its ok if you wanted that look
- the 70-200 its a super sharp lens even wide open, in portraits you dont need to be super sharp (skin blemishes and that stuff really pop out) so shoot close to 2.8, it will help you to isolate your subject (bokeh or background blur) and you could shoot faster to avoid blurry images
- use Spot focus and focus in one of her eyes (the closest to camera)
- Shoot a little far away, all the pics was at 70mm... try shooting at the other end 200... 135... if gives you "background compression" plus it shows a more "pleasing" proportion plus it gives you better bokeh!!!
- Always try to shoot 2 or 3 times the photo, It sucks when a "perfect" shoot its ruined by a quick blink
- Practice, practice, practice
Good luck and happy shooting