The next edges i'll extrude are highlighted.
Extruded...
Now I've extruded a face from the selected edge this will form a part of the nose and here's another Mesh update BaseMesh 5
I've extruded the edges shown here.
Next I've extruded the four highlighted edges.
Next extruded the five edges at the bottom.
Using the split polygon tool I've cut the faces here. And here's a mesh update BaseMesh 6.
I've selected these edges then extruded.
Just merge the edge here. Mesh update BaseMesh 7.
Extrude edges at the top.

 

Now at the bottom.
Extrude from the selected edges.
Select the 3 edges at the back here and extrude again.
Extrude the same edges.