Another vote for this book. Took me from objectively terrible at drawing, to objectively mediocre. I think if I'd put more time into practice it could have got me to the point of good. While this doesn't exactly sound like a ringing endorsement, it's literally the only thing that moved the needle for me.
I never made it through the book (I know, bad habit of mine) but she said _one_ thing in that book that opened my eyes; paraphrased "you're not drawing the object; you're drawing lines". The first time I drew a crumpled-up blanket blew my mind.
Since then, I just find techniques[1] and ideas[2] that I implement for fun. The reaction from people is joyous.
