first i added some color. i selected parts of the face and filled them with color and set the blending mode to color
step 2 of 4
then i added the glasses
step 3 of 4
i aslo made the eyes bigger and added some braces
step 4 of 4
then i added a glass look to the glasses by adding a light grey color and changing the opacity and then added a with brush strokes and blured them. then for the zips =) i just used a soft brush with a pink color and the added a yellow with a soft brush.