Practice makes perfect! FYI the concept of seams and unfolding hasn't changed much over the years; the unfold methods change sometimes, but smartly-placed seams never will. Sometimes with organic models, you may find it easier to make more cuts than you need at the start, you'll get a good idea after they unfold on how to…
That's what I thought initially... but I've watched it back over so many times and even slowed the whole video down to make sure I hadn't just selected a wrong edge or something. I even resorted to getting someone else to watch me as I followed along! :P I don't know if it matters much but the video is working with Maya…