How

How does the computer decide how to put a skin on a model? o_O I cannot figure it out. For instance, if you want to make a 3d smiley face, how do you draw the picture so that the eyes and smile will be on the same side. And if you want to make a guy with a sword, where do you put them so they go in the right place?

its called you uvwrapping
you do it before the skin
then the skin comes out as a grey wire frame and you do the designs and colors on it.
in game it does it automaticly...because it was pre wrapped that way...
if you want the face to be unsymetrical you would need lithunwrap,maya or 3dsmax to modify the unwrap