Meter for the light you can't control
I ran across this sentence in my notebook today and tried to remember what it meant. I had deconstruct the statement: the light you can't control... ambient light. The meter part wasn't simply about measuring, it was about creating your exposure based on the ambient light, and then adding the light you can control. In the outdoor setting, this advice seems simplistic and self-evident. For the above image I placed my model in the shade; then I under-exposed her a stop and adding a soft box with an SB800 on camera right to give more energy and shape to the light.
But you can apply this same principle indoors. If there are windows, the light outside is the one you can't control. French photographer (and Lightroom guru) Serge Ramelli makes most of his income from photographing hotel rooms. He has great advice about waiting for the Golden Hour before photographing hotel interiors. Turn off all the lights and see what the environment looks like, then building your lighting scheme around that.