when going to bed, the Prophet (saas) used to say: "Allahumma Rabbas-samawati wa Rabbal-ardi, wa Rabba kulli shay'in, faliqal-habbi wan-nawa, munzilat-Tawrati wal-Injili wal-Qur'anil-'Azim. A'udhu bika min sharri kulli dabbatin Anta akhidhun binasiyatiha, Antal-Awwalu fa laysa qablaka shayun, wa Antal-Akhiru, fa laysa ba'daka shayun', Antaz-zahiru, fa laysa fawqaka shayun', wa antal-batinu fa laysa dunaka shay', aqdi 'annid-dayna waghnini minal-faqr (O Allah, Lord of the heavens and Lord of the earth and Lord of all things, Cleaver of the seed and the kernel, Revealer of the Tawrah, the Injil and the Magnificent Qur'an, I seek refuge with You from the evil of every creature You seize by the forelock. You are the First and there is nothing before You; You are the Last and there is nothing after You; You are the Most High (Az-Zahir) and there is nothing above You, and You are the Most Near (Al-Batin) and there is nothing nearer than You. Settle my debt for me and spare me from poverty)."  

عَنِ النَّبِيِّ ﷺ أَنَّهُ كَانَ يَقُولُ إِذَا أَوَى إِلَى فِرَاشِهِ اللَّهُمَّ رَبَّ السَّمَوَاتِ وَرَبَّ الأَرْضِ وَرَبَّ كُلِّ شَىْءٍ فَالِقَ الْحَبِّ وَالنَّوَى مُنْزِلَ التَّوْرَاةِ وَالإِنْجِيلِ وَالْقُرْآنِ الْعَظِيمِ أَعُوذُ بِكَ مِنْ شَرِّ كُلِّ دَابَّةٍ أَنْتَ آخِذٌ بِنَاصِيَتِهَا أَنْتَ الأَوَّلُ فَلَيْسَ قَبْلَكَ شَىْءٌ وَأَنْتَ الآخِرُ فَلَيْسَ بَعْدَكَ شَىْءٌ وَأَنْتَ الظَّاهِرُ فَلَيْسَ فَوْقَكَ شَىْءٌ وَأَنْتَ الْبَاطِنُ فَلَيْسَ دُونَكَ شَىْءٌ اقْضِ عَنِّي الدَّيْنَ وَأَغْنِنِي مِنَ الْفَقْرِ  

the Messenger of Allah (saas) said: "When anyone of you wants to go to bed, let him undo the edge of his Izar (waist wrap) and dust of his bed with it, for he does not know what came to it after him. Then let him lie down on his right side and say: 'Rabbi bika wada'tu janbi wa bika arfa'uhu, fa in amsakta nafsi farhamha, wa in arsaltaha fahfazha bima hafizta bihi 'ibadikaas-salihin (O Lord, by Your leave I lie down and by Your leave I rise, so if You should take my soul then have mercy on it, and if You should return my soul then protect it as You protect Your righteous slaves)."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا أَرَادَ أَحَدُكُمْ أَنْ يَضْطَجِعَ عَلَى فِرَاشِهِ فَلْيَنْزِعْ دَاخِلَةَ إِزَارِهِ ثُمَّ لْيَنْفُضْ بِهَا فِرَاشَهُ فَإِنَّهُ لاَ يَدْرِي مَا خَلَفَهُ عَلَيْهِ ثُمَّ لْيَضْطَجِعْ عَلَى شِقِّهِ الأَيْمَنِ ثُمَّ لْيَقُلْ رَبِّ بِكَ وَضَعْتُ جَنْبِي وَبِكَ أَرْفَعُهُ فَإِنْ أَمْسَكْتَ نَفْسِي فَارْحَمْهَا وَإِنْ أَرْسَلْتَهَا فَاحْفَظْهَا بِمَا حَفِظْتَ بِهِ عِبَادَكَ الصَّالِحِينَ  

whenever the Prophet (saas) went to bed, he would blow into his hands, recite Al-Mu'awwidhatain, then wipe his hands over his body.  

أَنَّ النَّبِيَّ ﷺ كَانَ إِذَا أَخَذَ مَضْجَعَهُ نَفَثَ فِي يَدَيْهِ وَقَرَأَ بِالْمُعَوِّذَتَيْنِ وَمَسَحَ بِهِمَا جَسَدَهُ  

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."  

أَنَّ النَّبِيَّ ﷺ قَالَ لِرَجُلٍ إِذَا أَخَذْتَ مَضْجَعَكَ أَوْ أَوَيْتَ إِلَى فِرَاشِكَ فَقُلِ اللَّهُمَّ أَسْلَمْتُ وَجْهِي إِلَيْكَ وَأَلْجَأْتُ ظَهْرِي إِلَيْكَ وَفَوَّضْتُ أَمْرِي إِلَيْكَ رَغْبَةً وَرَهْبَةً إِلَيْكَ لاَ مَلْجَأَ وَلاَ مَنْجَى مِنْكَ إِلاَّ إِلَيْكَ آمَنْتُ بِكِتَابِكَ الَّذِي أَنْزَلْتَ وَنَبِيِّكَ الَّذِي أَرْسَلْتَ فَإِنْ مِتَّ مِنْ لَيْلَتِكَ مِتَّ عَلَى الْفِطْرَةِ وَإِنْ أَصْبَحْتَ أَصْبَحْتَ وَقَدْ أَصَبْتَ خَيْرًا كَثِيرًا  

that whenever the Prophet ﷺ went to bed, he would put his right hand underneath his cheek and then say, "O Allah, save me from Your punishment on the Day when You resurrect" or "gather Your slaves."  

أَنَّ النَّبِيَّ ﷺ كَانَ إِذَا أَوَى إِلَى فِرَاشِهِ وَضَعَ يَدَهُ يَعْنِي الْيُمْنَى تَحْتَ خَدِّهِ ثُمَّ قَالَ: «اللَّهُمَّ قِنِي عَذَابَكَ يَوْمَ تَبْعَثُ» أَوْ «تَجْمَعُ عِبَادَكَ۔»