Your institution is the best source of information on its Year 2000 readiness. Put your message there. You have signs. Put your message on them, and put a taped message about your preparations on your telephone system so that callers can listen to it while they re on hold. Train all your employees about Y2K and give them incentives to learn.
People receive a great deal of their financial information from their family and friends.
The more knowledgeable people you have out there, the more your message will spread. Consider displays in your lobby and outside your bank and on your ATMs. And open the bank after hours to customers to talk about your readiness. Make sure you invite opinion leaders, including the clergy. They have a pulpit week after week.