Riyad us Saliheen: Hadith 817

Whenever the Prophet (ﷺ) lay down for sleep at night, he would place his (right) hand under his (right) cheek and supplicate: "Allahumma bismika amutu wa ahya

[O Allah, with Your Name will I die and live (wake up)]." And when he woke up, he would supplicate: "Al-hamdu lillahil-ladhi ahyana ba'da ma amatana, wa ilaihin-nushur (All praise is due to Allah, Who has brought us back to life after He has caused us to die, and to Him is the return)."

[Al-Bukhari].