/ic/ - Artwork/Critique

Hey /ic/, so I've been trying to get down anatomy, and although I've been at it rigorously I keep fucking it up. When I draw from reference it seems to go okay but trying to draw anatomy from imagination it always turns out so angular and blocky. Like I try to get down some lines for the form but I almost always fuck up where the arm attaches to the body (armpitandshoulder) and the waist leading into the thigh. It just always looks soo unnatural to me. so now that I've bitched, I want to ask for some help, what anatomy studies worked for you guys? I just started reading through Bridgeman and I also picked up some Sheppard which has been helping better than Bridgeman. Any help would be appreciated because I feel stuck.