Just spent a long time replying to an anon who asked me about how to improve at anatomy and likeness, and then tumblr just decided to delete my answer </3, so I'm just gonna make a proper post out of it.
My biggest advice for improvement is to just get really, really, REALLY obsessed with something and then draw this certain thing non-stop until your hands fall off (please don't, do your stretches). Of course, doing proper anatomy studies is super important, too, but the second you decide to follow your heart and draw that yaoi ship that won't let you rest 24/7, you will see improvement in no time. And when you do sit down to do those boring studies? Draw your favorite character shirtless. Make those boring studies fun!
Here's some anatomy books I highly recommend:
These books have been the most helpful to me, especially Anatomy for Sculptors! Highly recommend just religiously copying every page from it. (These books can be found as free pdfs online, you do not have to purchase the physical version unless you want to. I know they're not exactly cheap.)
Here's some helpful websites/programs for studies:
Line of Action
Insanely helpful website with lots of study material. They even have an integrated timer and randomizer for all their reference material!
Grafit Studio on Gumroad
They offer a huge amount of anatomy reference packs of all kinds of poses and people. I've been using their reference for my studies for years! They do cost a little bit, but they also have a bunch of free test packs.
GestureDrawing!
A timer and randomizer for your references! Works the same as the one from Line of Action, though with this program you can use your own references.
It's incredibly easy to fall victim to "same-face-syndrome" but how does one avoid it?
Do studies of all kinds of faces! Old faces, young faces, asymetrical faces, round faces, long faces, square faces etc. You gotta draw faces that might not fall into our modern understanding of "beauty". I know, drawing conventionally hot people is super fun, I enjoy it as well, but if you want to improve at capturing likeness, you gotta understand all the little details that make a human face unique. Those deep wrinkles around someone's eyes, that little bump on someone's nose, that nice fullness to someone's cheeks. There's so much beautiful uniqueness to human faces, I highly recommend properly studying them. Look at an actor you like or a friend/partner you love and figure out in detail what makes their face the way it is, and try to think about how you would capture them on paper.
It's also incredibly important to understand the structure of a face. Where do the muscles sit that cause all of our expressions and how do they influence each other? What does the structure of the skull actually look like?
Here's two youtube tutorials that go into this more:
How I learned to draw better faces in a week by pikat
How I study heads/faces by Ullaiin
I really hope this was helpful! My inbox is always open for more questions! ❤️