the Prophet (saas) used to say: "Allahum-maj'alni minal-ladhina idha ahsanu istabsharu, wa idha asa'u istaghfaru (O Allah, make me one of those who, if they do good deeds, they rejoice, and if they do bad deeds, they seek forgiveness)."
أَنَّ النَّبِيَّ ﷺ كَانَ يَقُولُ اللَّهُمَّ اجْعَلْنِي مِنَ الَّذِينَ إِذَا أَحْسَنُوا اسْتَبْشَرُوا وَإِذَا أَسَاءُوا اسْتَغْفَرُوا