As an actor, you always want to represent yourself accurately. This may sound funny to be a number one tip, but surprisingly enough, some actors do not know this. They think that it is best to represent themselves the BEST they possibly can (i.e. no freckles, perfectly straight and white teeth, physically completely fit) when they are actually not like that. This would be fine if you never had to actually be on camera, and just your headshot did. But we live in a world where acting means that you have to audition for things, and that means that you have to be on camera. Not to mention that if you book the role, you need to look like what your picture is.
When you do not look like your headshot, you will find yourself in a predicament where you may not get called back for anything, which means you won’t book anything. This is a major issue, and if you aren’t getting called back, one of the first steps I would take is to look at your headshot and make sure that it is accurate. When a casting director calls you in, they do so because of your headshot. This means that they are expecting a certain person to walk in the door, and if you are misrepresenting that person, you may not be the right fit. A casting director calls people into audition based on their looks, and what other experience they have depending on how big the role it.
You need to consider getting new headshots every year or every two years. If you have a major change in your face (hair cut, teeth getting fixed, or maybe some work… it is Hollywood after all) you need to make sure that you get new headshots as soon as you can so that you can represent yourself as accurately as possible. This can seem tough, but I have had headshot sessions where the photographer used nothing but organic light with no retouching, and I was in love with the outcome. It is mostly about finding a photographer that you love and completely trust. When you have this person, you will be able to get a product that you like and are happy to send around to anyone who may want one.
Always keep your headshots as current as possible, this does not mean having them done every six months (that would be very high maintenance and also too expensive) but it does mean that when you change something major about yourself physically, or if you haven’t gotten new ones in over two years, its time to get new headshots.