One of the errors that I came across in my character template was that the face in the front and profile was not lined up properly.
The eyes, nose and mouth in the profile image were slightly higher up than in the front image. This meant that I had to decide on the relevant areas to have each part of the face without the adequate reference. I was still able to use the profile reference to decide how much Cornelius' mouth should come out and the angles at which his eyes were visible from.
To produce his nose and mouth area, I was originally going to create separate polygons, but I decided that it would be easier to model them from the face that I had just produced. I created the nose by cutting some edges around the nose area and then rotating the it out to make the round, flat shape. I created the nostril by exturding a face and scaling inwards.
The mouth was created by pushing the edges around the area inwards, making a more distinctive shape. and then extruding the faces outwards against the profile reference.
This is how the head looks at present.
Now all that is left is to model the ear, half of his glasses and then mirror the geometry.