...I totally did miss that. I think I did see a message about the "long-press F to save" in the beginning, but then I got to a bonfire and also saw "press F to save" and I guess inside my head, it just became "press F to save at a bonfire". With that knowledge (and a night's sleep), I came back to the game and managed to get to the end pretty quickly. That's definitely at least partly on me for completely missing that mechanic, so it definitely ups my enjoyment score of the game a couple marks!