年少轻狂不是错长发及腰不是我
[nián shăo qīng kuáng bù shì cuò zhăng fā jí yāo bù shì wŏ]
'Youthful Rashness Is Not a Mistake, Long Hair Down to the Waist Doesn't Suit Me.' It expresses a person's reflection on their youth - understanding past naivety isn't wrong, and long hair used to be part of self-image, no longer suitable for one's current stage in life.