The Messenger of Allah (ﷺ) used to stand at night (in prayer) and recite this supplication after saying 'Allahu Akbar':

سُبْحَانَكَ اَللَّهُمَّ وَبِحَمْدِكَ وَتَبَارَكَ اسْمُكَ وَتَعَالَى جَدُّكَ وَلَا إِلَهَ غَيْرُكَ

Subhanaka Allaahumma wa bihamdika, wa tabaraka 'smuka, wa ta'ala jadduka, wa laa 'ilahaa ghayruk

Glory is to You O Allah, and praise. Blessed is Your Name and Exalted is Your Majesty. There is none worthy of worship but You. Then he said this for three times -

Reference: Sahih (Albani). Abu Dawud: 775