The thing on his chest is a chain armor , made of hundreads of little rings . Since the is viewed from the side combined with the light and shadows, it's nearly impossible do recreate it on paper . The ammount of details is not the problem, the fact that there is no order , none is the same as the other, it's completely senseless. It was impossible for me to sketch them first , so I came up with another solution. I divided the vest into areas which are easier to draw separetely . You can see the lines I made . You can make your own or just follow mine .