tips...
it all depends on your modeling skills and your experience with maya (or whatever else you're using).
I personaly use poly by poly technique, extrude face, split polygon tool, delete some eges, merge some verticles and so...
but the first thing you must have when you start your model is an image plane. set it up and slowly start modeling from torso (that's easiest way for me to do it) and eventually using all the techniques stated above you might be pretty satisfied with the resul.
If the worst hasn't happened yet, that's because you haven't tried everything yet!