Portrait photography is like every other type of photography in that you need to understand composition, balance, flow, structure – basically, all of the elements of design. It’s unlike every other type of photography in that if you don’t like any of the elements that are present, you can tell them to move.
My best advice is to forget that you’re photographing a person, and concentrate on making a beautiful image first and foremost.
Some people will tell you that you need a particular type of camera or a particular type of lens. You don’t. You can use an ultra-wide angle lens, or you can use a super-zoom. You can use a disposable point-and-shoot or you can use an 8x10 view camera. It’s all about what you choose to put in the frame, what you choose to leave out, and the relationships between elements.