The Messenger of Allah (ﷺ) used to say:
اَللَّهُمَّ أَحْسَنْتَ خَلْقِيْ فَأَحْسِنْ خُلُقِيْ
Pronunciation
Allaahumma a’hsanta khalqi fa a’hsin khuluqi
Meaning
O Allah, you have perfected my creation, so too perfect my character.
Source: Sahih (Albani). Ahmad: 24392
Duas from IslamicAPI's Masnun Dua dataset (based on the Quran, hadith, Hisnul Muslim and Rahe Belayat). See the dataset