I can give you sooo many answers to that. In fact, we have so various Non-SFS threads that at some points I considered making a ho to draw stuff section.
Is not like I'm a Leonardo DaVinci or anything, but I kinda feel I can teach one thing or two.
The first thing you need to do is get rid of the rule, is simply impossible to draw a human with a rule (except Legman with a big maybeeeeeeeeeeeee) There are no straight lines on a human