Yeah, doing everything by the book is a valid way of learning, just might be too long one for one's lifetime. Nothing wrong with reference to Fowler, too. I guess, what @MoffKalast mentioned, that it looks like kinda overkill for a single developer's project. What I wanted to add is that UML was kinda overestimated as a tool being introduced - and, as it was initially designed with really monstrous workflows such as RUP in mind - especially for small-to-mid sized projects. It was still too technical for managers (and they now have BPML to play with, lol) and not that much quicker to read for coders than the code itself, so..
I mean, sometimes a quick-and-simple focused picture might just suit better than something bigger, but approved by ISO.