LOOK TO THE LIGHT
With directional light (whether indoors or out), it's always important to know where your light is actually coming from. Seems obvious, I know, but sometimes the obvious things need to be said and heard. Knowing where the light is coming from is the first step in using in it to your advantage. One of my favorite little directions for models is to find the light (meaning to aim their face towards it). With directional light that creates a bit of mood while still leaving a luminous, flattering light on your model's face.
5D III + 50L
Ready for some secrets? This frame wasn't shot in a studio. It was actually shot in an alley with with a white wall in front of her, reflecting light in from above. Since the light was pretty directional from the top right (her right), I had her look up towards it so she had light in both of her eyes. That left soft light on her face, and defined her bone structure a bit more.
5D III + 50L
This was frame was all about playing for me. We are artists and get to create whatever the heck we want to I set up a day in the studio to experiment for the sake of having fun. In this image, I was shooting through plastic sheeting which was hung in between us. The light was coming in from a window on her right so I had her look in between the window and my lens. That gave a more dramatic side light while still lighting up the blue in her irises. Win-win!