What you can also do, is to simply Booleaning the shapes together (Union for the ear and Difference for the mouth) and not care about Topology, Bevels and smooth transitions yet. Then Apply the Booleans and do a Retopology, starting with the ear and mouth, so that you get something that you can Bevel.
So, you split up the complicated work in two simpler parts; first the shape and then the Topology.
