I recently got a pin vise from USA Gundam on Ebay. A pin vise is pretty much a hand Drill. I used this tool to drill holes into areas of the arm, chest, and machine gun. I did this to make areas that holes in them, have holes in them instead of just painting them black.
Then today, I did some light sanding on the chest and then painted it.
I do like the effect it adds to the chest.