Less is more. We have heard that a million times in all areas of life, especially in the acting business. Well, it has never been more true when shooting your headshots. Really. Less is way more. Think about this: the casting director already has the story in their head and they are looking to fit someone into that story. You are either it or you are not. No need to push. No need to be big. Just be. Let the clothing, the light, the mood, and your thoughts point the viewer in the direction you want them to go. They will go there with you if it all matches up and the shot is specific enough to fit into the story without you, the actor, distracting them from trying to place you in their story. Don't distract by pushing. Just be and let everything around you help fit you into that story.
Peter is one of the top headshot photographers in Los Angeles. He's been around for over a decade and is recommended by numerous casting directors, agents, and managers. Check out his portfolio at http://www.peterkonerko.com.