Hey, I'd be willing to help you out~
(to be honest I'm
still learning how to draw humans as well, so I'm right there with ya..)
WARNING-Incoming Critique
A couple pointers anatomy wise, the neck is a bit long and the arms are a bit short. Hands usually fall a decent distance below the waistline.
Try adding a couple tufts of hair showing out from behind his head to give a better impression of the longish-shortish hair you're doing (if that makes any sense XP)
The pockets look too small for the hands, so maybe try expanding them a bit?
And, if you can, try to make the necklace look more 'flow-y' and not so tight, as right now it looks almost like a choker...
~~~
Hope that helps~
If you need/want anything else feel free to ask ^^