The Nose

After the mask has been created using symmetry and turbosmooth modifiers, the nose area needs to be filled in a shaped. The picture below shows how the polygons look after being added and positioned. The nostril is initially made flat along the bottom of the nose, then is pushed up and in by extruding the relevant face.

 Once the shape of the nose is satisfactory, the turbosmooth modifier can be reactivated in the stack.

 

 I managed to get the shape of the nose working quite well, but it needed a lot of tweaking to make it look like mine. The images below show the improved shape. 

This tweaks are much better than the original shape, but it is still not perfect, so further tweaks will be made throughout the project on facial features like this.