See the little dappled bits in the background? Salt does that. Put it directly on the paper while the paint's still wet, and it sucks up the water, and thus some of the paint, around it. Can be used in clumps for texture, or sparsely for a snowy look. Fun stuff. ^^
Wow!!! Wonderful! You captured his feature/presence so well, and there's this air of south-east Asian from his realistic face. I'm been drawing him in very anime/cartoonish style, it's good to see him drawn this way- adds a new perspective.