What do you recommend as a first step for hands-on learning about flash?

Question

So far, I am enjoying my new Speedlight (Nikon SB-700), but any good results I have gotten have been mostly luck. I'd really like to understand how to use it so that I can make intentional technical decisions (as opposed to relying entirely on accidents and tweaking).

Assuming that I have a decent understanding of ISO / Aperture / Shutter in non-flash photography, what would you recommend as a very first, hands-on step to systematically explore how to use my setup in flash photography?

I am perfectly willing to take 200 consecutive photos of the same object if you think it is instructive to do so.

(As part of the answer, I'm also looking for settings: TTL vs Manual vs Distance Priority? Manual exposure mode vs Aperture- / Shutter-priority? Center-weighted vs spot metering vs matrix? Slow/rear/no curtain sync?)

Answer

Easy. Strobist website Lighting 101

For specifics to Nkon CLS - Nikon CLS Practical Guide

For systematic assessment of ambient vs flash and other things, Neil van Niekerk's books On Camera Flash and Off Camera Flash

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