These are all good tips, and important for target shooting competition when forced to shoot offhand. I always did well hunting with open sights at shorter distances. (under 100yds)

However, if you're using a scope with longer shots and high magnification for hunting. I don't see the need to shoot offhand. If you don't have sticks, you can always find some kind of rest. If not going to a knee, or sitting is better than offhand.

Just rest the gun on your buddies head if you have to.