Rounding off the edges 

The next step is to start creating some depth between the different parts of the face.  Using a medium loop tool gently start carving away the corners of the cats mouth.   

Tip:  When you carve the corners of the mouth you want to create a 45 degree angled slope.

Rounding out the eyes 

I next move onto the eyes repeating the same steps that I used for the mouth.  The goal here is to round out each of the facial features.