First things first: I am not very good at drawing him either :’D
I suggest you do lots of studies of him with references on the side, especially at the beginning. Once you start to get the hang of it, yuou can pull references aside if you wish. They do always help. Also make you realize how different he actual is in-game from how I draw him :’D
Also, the true secret to all drawings is practice, so you need to draw lots, k?
I don’t know when I started to draw his horns so differently from the ones he actually has but I’m not complaining. unless someone else is complaining. But hey, you just need to find your way of drawing them 😀 and once again it’s all about shapes.