I avoided making a tutorial about this area because I am not really into the technics of studio lighting, usually I just set up the lights and do whatever, and don't even use a light meter. But I am still guided by the basic studio lighting set ups, this
website gives a good summary of basic studio lighting techniques.
In my picture below, I used a butterfly set up as the main light to his left (the white arrows coming from above). This is actually a 3 point lighting technique, as the light bouncing off the wall filled in some light on his cheek (the one in shadow).

You can see this light reflected in his eyes, it was an ellinchrom studio light shot through an umbrella. To outline his head I positioned another studio light further way from him to his right, and shot it in the angle as outlined in the arrows. Have a back light is essential to reduce flatness in your portrait, its good for giving your portrait more depth, as well as outlining the hair of those with dark hair. Angle is important too, generally I shoot from below the chin with a male as it gives them a squarer, more rugged jawline. If you do this for a female it often creates a pudgy looking double chin, and your female friends wont appreciate this! There are many many face...