The cheekbones are a pain but in the end it just takes a bit of patience. Have a look at Antman's second scratchbuild thread, it shows it in a good bit of detail. The little cuts on the inner surface are really useful. I have seen some guys put more than one in to help shape the pieces.
As you will be filling out the cheek area with bondo/filler later, don't worry much with any creases you get. If you are using cardboard, like I did, moisten the cardboard, shape it then I used a hairdryer to thoroughly dry the cardboard before trying in. moisten it and shape it again. Make sure you keep drying it or the edges will fray on the cardboard. When I had a fairly good shape I taped the rear straight part on then carried on shaping the rest with this bit secured in place. Once I had a good shape I dried it then glued it. I've had to do a fair bit of filling, sanding and shaping to get the correct shape, but I'm pretty happy with it now. Hope this helps.