They won't believe what you say. They will believe what you do. But, even if what you do matches what you say, you will eventually falter if it doesn't match your own fundamental beliefs. This is why "Be Do Say" leadership is so powerful.
Working harder is often counter-productive. If the scope of what you're trying to accomplish is too much to get done in a high quality way, say "no" to some of the less important items and non-value-adding steps.