Solid colours photograph better than patterns, but not because patterns are forbidden - it is that a busy shirt competes with your face for the viewer's eye, and your face should win. Mid-tones do the most work: they separate you from both a light and a dark background without anyone noticing the trick.
Necklines matter more than people expect. A crew neck reads younger and more commercial; an open collar reads older and more authoritative. Bring one of each and we will shoot both.
Bring six to eight tops for a two-look session. We will use three.