Create a manual or handbook to address the potential problem areas. The handbook should serve as a rulebook to instruct your employees about how each situation should be handled. For instance, you can document in the handbook that the employee is to never, under any circumstances, argue with the customer. List a rule that the employee is to acknowledge every customer by greeting them with a smile instead of ignoring them. More sample rules are no talking on the cell phone while customers are around and apologize to customers who report negative experiences.