By all means tell the world how good you are — but share the credit and reserve the blame.
A fundamental principle of leadership that has not changed over the centuries is: Share the credit for success with others, but take the blame for failures alone.
It is virtually impossible to conceal the truth forever. It is the natural order of things that the truth will eventually come out. This single fact is the foundation of our judicial system and the basis on which all human relationships are formed. A business, professional, or personal relationship built upon a lie cannot long endure, but one that is founded on truth and equality of benefit for the participants is unlimited.
Make it a practice to tell the truth in all that you do — even when it doesn’t matter — and you will form a habit of truthfulness. You will know instinctively that it is better to tell the truth and face the consequences than to launch a falsehood that will eventually make itself known to the world.