There's a little more to it than just the camera angle.
You'll need to learn how to guide your subject into a flattering pose. For a start, do a Youtube search for Peter Hurley's "It's All About the Jaw" video. In addition to his tips, angling the hips and shoulders of a standing subject can help elongate their neck and give a more defined jawline, which is desirable on just about any sort of portrait.
After that, portraiture is about lighting. Short lighting and broad lighting are two techniques to learn off the bat; one of those two techniques will almost invariably allow you to get a pleasing face portrait on just about anyone.
There are lots of posing and lighting guides out there - but many of them are very subjective, or dated to that era's style of portraiture. Much of it will come with experience, and really studying portraits that you personally find to be pleasing or unflattering. What makes a portrait good or bad?
One of my first and most important portraiture tasks was to figure out how to eliminate a double chin. My wife isn't fat but she doesn't have much definition in the chin or jawline. With effort and study, I can now almost always take a good shot of her that flatters her and minimizes the double chin.