A practical way to compare hair shades

I have booked my first proper color appointment, and I am trying to arrive with a useful description instead of a heavily edited photo. The hair I have now is a fairly ordinary brown and my skin is fair, so I am considering a cooler change rather than a bright copper or golden blonde. The photos on my phone make every shade look more polished than it might in daylight. I cannot tell which of those shades would still look balanced when I am outside or under office lighting. I want to narrow the choice to a couple of shades. I would prefer a result that can grow out without urgent touch-ups. I am using cool summer hair color ideas as vocabulary for the consultation, not as a strict rule about what I should choose. Would it help to compare sample swatches against my face? I can take pictures in natural light, but I am unsure how much to trust a phone camera's color balance. The appointment includes a shorter cut, so I would rather make the color decision thoughtfully than change everything at once. Starting subtly might help me learn what actually suits my routine. If you have made a similar first change, what did you ask your stylist before mixing color? I am especially interested in how you weighed everyday lighting, upkeep and the condition of your own hair.