CAT - Mod - 3 Creating the face

I 'lifted' the mouth up by extruding the above vertices and shaping like a head. Proportional editing was very useful, one can shape the vertices around the selected area and keep it all relative.

I had previous experience that sometimes when using the subsurf modifier
black blocky lines would appear, I learnt that by recalculating normals you can eliminate these. (EDIT/select all/CTRL N)