To begin, notice how the light is already hitting the subject. Decide how I want to change the light in order to make a better looking image. Bounce light off the walls near me either to the right or left usually angled around 30 or 45 degrees. Use exposure compensation in TTL mode to add or subtract light. Meter off the ambient light, if the ambient light is the same as light on subject...meter 1.5 to 2 stops less. If the ambient light is brighter than the subject, meter of the brighter ambient light behind the subject. In this scenario I want to have less light in the background I can either change my aperture or my ISO to get desired effect. This is because I am working in TTL mode on my flash, if I had been working in Manual flash I would drag my shutter speed. In low light situations have the shutter speed be at least 1/10 to 1/20th of a second to make sure I get a sharp image.
So, if I have almost a correct exposure, but the contrast between the highlights and shadows is to much, then I can use my flash as Fill-Flash to lift that contrast. I would then bounce light behind me just to lift a tad. I think!
Here is a cute baby, since this stuff is pretty boring! Plus posts are always better with images!