Use a light meter
In camera metering is great, but it doesn’t account for multi-light setups, nor can it help you nail your exposure on the first shot, or properly expose hair lights or background lights with a breeze. Just because you know how to read a histogram doesn’t mean you shouldn’t use a light meter, it will take the headaches out of lighting.
Come to our lighting and editing workshops and learn how to use a light meter. See details fo the workshops here... http://northof49photography.com/lighting-and-editing-workshop