also, you did some black lines almost everywhere in the armor, im highly against that, it looks extremly bad. try blending it more into the armor, thus it would look less natural. and your shading lacks of dynanism and accuracy, pratice it a lot. i realize you're probably at your beginnings, but that shan't be a reason. try adding shading to the yellow, everything can be shaded and darkened, when it's black, then it can be grey-like. shading is very, very important, a lot of beginners understimate it.