please plaese since you have the original at hand do not lower yourself to draw from a picture. It's so much better in the end even though at first sight the pic might be easier (wrong wrong WRONG) so go ahead. My best portrait is an oil painting direct from a guy who used to be a boyfriend (hahaha shame on me) but with no prior drawing neither sketch or whatever - but you catch the real thing that way. Go ahead and better do not try to do anything finished just lots of different fast done ones.