Is SO important in this business! Make sure you're face is straight towards the camera. The Client wants to see the shape of your face, nose, eyes etc. Be relaxed! A forced expression is easily detected. Don't wear stripes or crazy patterns to distract from your face, Your face is what sells you, so let it stand out, and remember, all feelings start with the eyes. Whatever expression you're going for, feel it in your eyes, and your face will follow.