Well you need to have two pictures, something like this:
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|
|
|

'-' stands for a front view picture
'|' stands for a side view picture

You can't use the front picture as a side picture because you won't create the depth view at that way, you would just have the same picture but different coordinated. X and Y will create the depth when working at this methode.
Try searching for a two different facial pictures when working with faces, a front, a side view and eventually a top view too but it isn't necessary. I mention a top view because this is just for refering to the right shape as a recheck Just google for it

Cheers

Frazzle