the Prophet (saas) said to a man: "When you go to lay down, or go to your bed, say: Allahumma aslamtu wajhi ilayka, wa al-ja'tu zahri ilayka, wa fawwadtu amri ilayka, raghbatan wa rahbatan ilayka, la malja'a wa la manja'a minka illa ilayka, amantu bi kitabikal-ladhi anzalta, wa nabiyyikal arsalta [O Allah, I have submitted my face (i.e., myself) to You, and I am under Your command (i.e., I depend upon You in all my affairs), and I put my trust in You, hoping for Your reward and fearing Your punishment. There is no fleeing from You and no refuge from You except with You. I believe in Your Book that You have revealed and in Your Prophet whom You have sent).' Then if you die that night, you will die in a state of the Fitrah (nature), and if you wake in the morning you will wake with a great deal of good." (Using translation from Ibn Mājah 3876)
عَنِ النَّبِيِّ ﷺ قَالَ إِذَا أَوَيْتَ إِلَى فِرَاشِكَ فَتَوَضَّأْ وَنَمْ عَلَى شِقِّكَ الْأَيْمَنِ وَقُلْ اللهُمَّ أَسْلَمْتُ وَجْهِي إِلَيْكَ وَفَوَّضْتُ أَمْرِي إِلَيْكَ وَأَلْجَأْتُ ظَهْرِي إِلَيْكَ رَهْبَةً وَرَغْبَةً إِلَيْكَ لَا مَلْجَأَ وَلَا مَنْجَا مِنْكَ إِلَّا إِلَيْكَ آمَنْتُ بِكِتَابِكَ الَّذِي أَنْزَلْتَ وَبِنَبِيِّكَ الَّذِي أَرْسَلْتَ فَإِنْ مُتَّ مُتَّ عَلَى الْفِطْرَةِ