For the Business and Performer Photo Shoots, the best advice we can give you is to keep it simple.  Wear fitted clothing that you feel comfortable in, and avoid any distracting patterns, colors, logos, etc.  Stick to your choice of light or dark, solid colors.  For black and white headshots/portraits, it's important to wear clothing that contrasts with the color of your skin... or the results will be unimpressive and will looked washed-out.  Dress according to the image you wish to present.