Jason,(posted 9228 days ago)I do agree with Michael that a relaxed model is *the key* to a great portrait. My experience with portrait shooting is very limited (in fact just 2 photo sessions, having my parents as victim^H^H^H^H^H^H willing models:) and I have no access to pro lights, just to a 6x6 camera with a 80mm lens, tripod mounted, a Spotmeter, available light and a white sheet of paper used as a reflector, to feel the shadows.
Didn't use any trick with the exposure. Just the usual 'expose for the shadows, develop for the highlights.' The sheet of paper proved to be very useful, to bounce the main light and create the proper balance between light and shadows (B&W depends on contrast).
I run my 2 photo sessions with Kodak Tri-X pro (320) developed in Xtol 1+3. It worked great for me, with very very nice negatives and beautiful skin tones. Of course it may not work for you, since the choice of film (and paper) is very personal. I don't feel the need for fine grain film with MF negatives... the prints were made on AGFA Multicontrast classic (MCC111) toned in Kodak Rapid Selenium toner, 1+3. I got a couple of photos I am not ashamed of. You can see an example in http://geres.adm.uminho.pt/~ricardo/mae.jpg
My tips for you are: Enjoy yourself, take notes on what you are doing, so you can correct mistakes later, take your time to 'explore' the model. The results will depend more on your creativity and on your skills then on your equipment, imho.
Just my 2 cents.