where to put edgeloops?

hey i was just wondering i saw torqs edgeloops tut but i just dont get how he knows where to put the edgeloops in the picture, if anyone knows please let me know

Fudge

If you look at meshes of head models done by pros you will notice that the edge loop patterns are all quite similar. That’s because the patterns are based on the muscle structures of the face (allowing for similar deformations in animation). The patterns are parallel and perpendicular to muscles – not diagonally across them. TorQ’s tutorial sets up edgeloops that follow this practice and that is why his facial animation looks so nice.

In general, if your mesh is going to deform due to animation, it is better if your edgeloops are parallel and perpendicular to the deformation. The mesh will then appear to deform more naturally.

GreyBeard