To make the foot, simply select the last row of vertices and extrude them.
Scale and reshape.
Select the last row of vertices, hide all the others, and reshape them in
a foot's style.
Builf faces to close the shape.
To make the arms and shoulders, select some vertices at the left, Extrude
and reshape them like the image above. Before the Extrude down action to
make the arm, you must have a close line ( like the hip previously).
Now, that you have the body basic shape finished, it's time to refine the
model.
This little point it's... just one of the most important. It's here that
your modelling skills make the diference. Refining little details it's very
important, specially if you'll animate the character.
Blender gives you a helpful tool: the Proportional Vertex Editing. Select
one or more vertices, press O key, and control the amount of influence (
doted circle area in the image above) with + or - keys.