If you've ever seen the picture of the author in the back of the book, then you are already familiar with a press photograph. A press photograph is one that is specifically taken for public release. You do this with a professional photoshoot; a photoshoot with a photographer that has experience with taking professional photos. You should be able to tell the photoshoot photographer what you are trying to achieve, and you should come away with a photograph that achieves that goal.
When it comes to a press photo, you want to make sure that you meet certain qualifications with that photograph. You can definitely get someone to do a photoshoot and shoot professional images of you that can be used for press photos. But they have to be told in advance that that is what they are shooting for. If you have someone that doesn't know what they are doing, doesn’t bring the right backgrounds or doesn't know what kind of pictures they are taking, then your press photos are going to turn out very badly.
Let's talk for a moment about how to take the right press photo. A press photograph of a specific person is going to show their best features. A photographer will know more about how to show the best features. They'll be able to place the right background and props or frame the picture correctly in order to show you in the best light.
Do you want to be seen as someone who has information and power within the industry? If your photograph looks like someone who could never run a company, but you are CEO of a major organization, then you need to get new pictures taken, because your photo should be able to show you in the light that makes you look your best and gives people confidence in the company in question.
The clothes that you are wearing will factor into what kind of picture you can take, but the main job of the photographer is to get you in the right location and get you in the right position. You will likely be choosing your own wardrobe. From there they will take the right photographs, and capture your best moments so that when people look you up online, they will only see you at your best.
Much of what you do during a press photography session will depend upon the photographer; that is why it is so important to choose the right photographer for your session; everything from the background being used, to the expression on your face, will be judged by those who see the photograph.
You need to be able to convince them of whatever the photograph is trying to convey. For example, a book written by a medical expert would probably have a press photograph of the author in a lab coat, because that will inspire public trust and let people know did he or she is a medical expert.
Your photograph should do the same thing, meeting whatever goal you're trying to amplish when you set up the photoshoot.