How to start?

My 3 year old Kenmore Quiet Guard/Standard dishwasher won't start. I've hardly used it since it was installed so the machine is still in excellent condition. I set the dial to the desired cycle and press start and nothing happens. The door is latched securely. My lights go on, but when I press start, the lights go out. I have no manual. I don't think anything is broken, I think I just don't know how to turn it on. DUH! What is the proper way to turn this dishwasher on?