Reference : Hisn al-Muslim 111

اللّهُـمَّ أَسْـلَمْتُ نَفْـسي إِلَـيْكَ،
وَفَوَّضْـتُ أَمْـري إِلَـيْكَ، 
وَوَجَّـهْتُ وَجْـهي إِلَـيْكَ،
وَأَلْـجَـاْتُ ظَهـري إِلَـيْكَ،
رَغْبَـةً وَرَهْـبَةً إِلَـيْكَ،
لا مَلْجَـأَ وَلا مَنْـجـا مِنْـكَ إِلاّ إِلَـيْكَ،
آمَنْـتُ بِكِتـابِكَ الّـذي أَنْزَلْـتَ
وَبِنَبِـيِّـكَ الّـذي أَرْسَلْـت
Allāhumma aslamtu nafsī ilayk, 
wa fawwaḍtu amrī ilayk, 
wa wajjahtu wajhī ilayk, 
wa alja'tu ẓahrī ilayk, 
raghbatan wa rahbatan ilayk, 
lā malja'a wa la manjā minka illā ilayk, 
āmantu bikitābika ‘l-ladhī anzalt, 
wa bi-nabiyyika ‘l-ladhī arsalt.


O Allah,1 I submit myself to You, 
entrust my affairs to You, 
turn my face to You, 
and lay myself down depending upon You,
hoping in You and fearing You. 
There is no refuge, and no escape, except to You.
I believe in Your Book (the Qur'an) that You revealed,
and the Prophet whom You sent.

Reference:
1 "Before you go to bed perform ablutions as you would for prayer, then lie 
down on your right side and say. . . "
The Prophet (ﷺ) said: "Whoever says this and dies in his sleep, has died 
in a state of the natural monotheism (Fitrah)." Al-Bukhari, cf. 
Al-Asqalani, Fathul-Bari 11/113, Muslim 4/2081.

Chapter: Before sleeping