It is narrated from Sayyiduna Ibn Mas'ud (may Allah be pleased with him) that when the Messenger of Allah (peace and blessings be upon him) looked into the mirror, he would recite this supplication: «اَللّٰهُمَّ أَحْسَنْتَ خَلْقِي فَأَحْسِنْ خُلُقِي» "O Allah! Just as You have made my appearance good, make my character good as well."