This has actually been in my "to post" pile for a while. Now here it is!
As someone who's been drawing furries for 10 years, I will be the first to tell you that I'm uh, not great with human faces! But I want to change that.
Recently I found artist Modern Day James, and proceeded to have my mind completely and utterly blown by his method and mindset when it comes to art. With deep roots in perspective, knowledge of camera angles, and an appreciation for being able to replicate objects from multiple view points, I feel like this guy is an answer to prayers I didn't know I had; sketching with spheres and organic shapes has always felt really good to me, but using cubes and perspective tricks to create those organic shapes, and better understand what they represent? That feels even better.
As you can probably tell from the image up top, I checked out the videos in his anatomy playlist, starting with starting with the anatomy of the head. This post is just some of my sketches and notes from following along.
I used the resource BioDigital for the skull images scattered throughout.
Here's me getting way too hyped about finding this stuff and trying to Learn All The Things, haha.

Very helpful, though.
Did I mention I love drawing skulls?
On another sitting, I slowed down a lot, drawing fewer things, but with more purpose. Also, taking notes. Take notes! It really makes a huge difference in retaining information.

Sorry for my hand writing haha.
After that, I moved to... well my intent was to do various features, but I really just got stuck on eyes. I won't complain too much, though, because I know that learning this human anatomy will make drawing animal anatomy easier too. Learning is learning.

Switching between drawing from reference and drawing freehand is way more helpful than you might think. It's pretty much like taking a quiz after reading a passage. Whether you get it right or not, just trying to answer those questions - how does this look, what way does this form turn, what lines should I emphasize - embeds information in your mind much more than if you hadn't.
It also just makes me feel really accomplished!

For both of these days, I think I was sick, so I wasn't able to do very much. I did, however, cement the idea that using boxes is way, way more helpful for me than spheres. I just don't feel like I'm able to measure where features should go without hard edges.
I'll have to expand on that another day, though! I might try some animal skulls next, hmm.