Starting a new drawing

today, i am starting to make a new drawing. the drawing will be of a pretty girl in a 3/4 view of the head.
i used my ideal method for drawing heads,
in this method you divide the head into three equal parts, top of forehead to eyebrows, then bottom of the nose and then bottom of the chin.
the perfect face. to bring difference from other faces mess with the proportions a bit.
and walla... you have a properly proportionate looking portrait