Thank you! I'll repeat this until I turn to dust: Draw from life. I've done that since I was a kid, just looking at stuff and trying to make it look like the photo or the thing in front of me. I spent many hours seated in front of my Legolas poster trying to get his lips just right. I wish I had a more in-depth answer for you and maybe there's things I could have done along the way to speed it up or hone my focus better, but really just looking at a body/pose and noticing the little details and filing them away as you draw it does pretty well. I have... not really looked up tutorials. I do for environments and stuff but for anatomy I'm pretty strictly observation. I have one of those Phicen silicone dolls that's good for large-brushstroke posing.