A Lannister always pays his debts.
You can't build a reputation on what you are going to do.
Be more concerned with your character than your reputation, because your character is what you really are, while your reputation is merely what others think you are.
It takes 20 years to build a reputation and five minutes to ruin it. If you think about that, you'll do things differently.
The most important thing for a young man is to establish a credit - a reputation, character.
Do not leave your reputation to chance or gossip; it is your life's artwork, and you must craft it, hone it, and display it with the care of an artist.