You will need to use SimPe to be able to extract that sim.
Here is a tutorial explaining how, just follow all the directions in the Step 1 part:
Tutorial-Giving your in-game sims a permanent make-overIf you make it in Bodyshop, there is a package sim option coming with that tool so you would not need to do this, but it is really easy to do, you'll see.

Oh and just in case, Sim-Pe can be found here:
Sim-Pe