They key is proportions in theory it is 
an easy thing to say but doing it, is different, people draw with rulers
to help with their dimensions, once you have done it long enough
you wont need the rulers, it then becomes a habbit, but starting off??
I'm not going to lie to you, artist mentality is live above the law and out side the rules, because we think outside the box, but truly, Art has rules as well, if you want to round yourself out practice at least 30 minutes a day with a ruler and you will see a lot, you may even began 2d and 3d perspective drawings by yourself, which for me was a hard concept to master when you are self taught,
Realism and photography both help master the concept, but actually
drawing,
"wash , rinse, and repeating,"
will help you master this quicker,
Once you got the lines down everything else is a piece of cake!!
Enviroment and perspective are importand factors to character development, simply because the development part, is the personality of the figure, what are they like?, What do they do, where do they go?
Pictures should answer these questions,
it doesn't matter how, because no one can see the mind of an artist until it's on the paper, so make sure it's clear, concise, cohesive, use rules,
it's for the eye of the beholder.!
--
B.Alon Brownwww.alonbrown.ga
