When staffing a booth, salespeople have the tendency to fold their arms, put their hands in their pockets, or put them behind their back. As a salesperson working an exhibit you have 4 seconds to create a positive impression. Immediately looking at visitors' badges does not create warmth and comfort, because it appears that you are evaluating them. The success tip is to always make eye contact, introduce yourself and shake hands. Then it's appropriate to glance at a visitor's badge, after you've established rapport.
Prospects generally avoid interrupting salespeople talking to other sales reps in the booth.
Our parents have always taught us not to interrupt. So when prospects walk by and see two salespeople talking, they will not approach the exhibit. Strangely enough, prospects won't hesitate to approach a salesperson who is alone, but busy. For example, a customer in a retail store will approach a salesperson stocking merchandise. The tip here is to avoid clustering.