You ussualy place the joints in a position that would mimic the joints in the animal.
Use whatever workflow you feel happy with, I like to poly box model heads and arms, torso as sepperate objects, keeping into consideration how to connect them, then combine them and tweek. Although I will sometimes extrude edges if I feel like it, thats just my workflow and what works for me.
"No pressure, no diamonds" Thomas Carlyle