:D ok! i’ve updated the Sonic character anatomy, this is basic though but i really hope is easy to understand (because i’ think i’m not good enough explaining things with words lol) and it results useful to anyone who might need it ^_

just some other tips to improve:

try drawing comics! on comics you have to try new poses, angles and expressions.. is reaally helpful to improve your drawing skills!
look at official art for reference
listen to cool music! XD it always helps to get inspired hehe
here are some other tutorial things from before:

Rouge / Amy and Silver’s quills / Sonic and Shadow’s quills / neck and shoulders