Dua before sleeping

اللَّهُمَّ أَسْلَمْتُ نَفْسِي إِلَيْكَ، وَوَجَّهْتُ وَجْهِي إِلَيْكَ،
وَفَوَّضْتُ أَمْرِي إِلَيْكَ، وَأَلْجَأْتُ ظَهْرِي إِلَيْكَ، رَغْبَةً
وَرَهْبَةً إِلَيْكَ، لاَ مَلْجَأَ وَلاَ مَنْجَا مِنْكَ إِلَّا إِلَيْكَ، آمَنْتُ
بِكِتَابِكَ الَّذِي أَنْزَلْتَ، وَبِنَبِيِّكَ الَّذِي أَرْسَلْتَ

O Allâh, I have entrusted my life to You, turned my face to You,
entrusted all my affairs to You, and have totally placed my reliance
on You. All this I do to gain Your mercy and out of fear for Your
punishment. There is no protection from Your wrath except through
Your mercy. I believe in Your book which You have revealed and in 
Your apostle which You have sent. 

Reference: 

  • (Bukhârî)