Nine mantras short enough to stick, substantive enough to practise.

1. "This too shall pass." — Persian Sufi proverb. Works for both good and bad times.
2. "Start where you are. Use what you have. Do what you can." — Arthur Ashe.
3. "Progress, not perfection." — AA.
4. "Small steps, daily." — compounding in three words.
5. "Be kind, for everyone you meet is fighting a hard battle." — attributed to Philo.
6. "You cannot control what happens to you, but you can control your response." — Epictetus, paraphrased.
7. "Nothing is permanent." — Buddhist anicca. Both comforting and sobering.
8. "Just begin." — the hardest two words.
9. "Be here now." — Ram Dass.

Pick one. Write it where you'll see it daily. Mantras that actually change lives are ones you've repeated a thousand times, not ones you've collected.