Today i spent about 30 minutes trying to begin to work on a smile and narrow shape. I made this in photoshop using zbrush to model the base geometry... soon i'll begin working on the rigging topology for Joy's face.
some things i found helpful were
-- to feel comfortable discarding a 2D layer if it doesnt seem to be working
-- try to see whether the final look if it was in 3D would it look cool
-- for mouth since this was a more medium style head not too cartoony, lips didn't move much in head which is why it was possible to lower opacity of background Zbrush model and still be able to draw lips in a different pose.
i do want to learn how to easily paint add on's modifications to sculpt in photoshop .. like figuring out a nice soft paint brush and cool way to paint without too much contrast ... I also want to learn how to use the c++ api to make context tools to allow topological modeling on-top of an imported Zbrush mesh easier.
In these images i'm beginning to learn to iterate on a 2D design to inspire a 3D rigged face later on.
Inspired by Mark Simon's: Facial Expressions A visual reference for artists