I've always liked how Chuck looks in Seed Of Chucky, his expressions are more realistic looking and I like how whenever he's angry near the end, his eyes had the red veins in them.
Well i use graphite pencils, just two for some of my pictures, all graphite pencils have different shades... i recommend getting those... one of the small packs tho... they are expensive!
and do not draw with you picture lying down cus it won't look the same when you stand it up.... i've made that mistake some many times..... only lay it down when your shading it in....