This skin is made up of some of my favorite blocks in Mine Craft. The pants are meant to be dirt. The shirt is obsidian. The shoulder pieces are pistons. The bandana is supposed to be leaves. And the helmet is a horrible representation of cobblestone.
There is also a dirt block emblem on the front of the shirt, and an iron pickaxe attached to the back.

Things to do:
Change pants and helmet colors to better match corresponding blocks.
Redesign iron pickaxe to make it smoother.
Make the helmet a separate part from the head.
Change eye color.
Add shading where necessary.
Make sure insides of arms/legs/head looks good.