In the evening recite

أَمْسَيْنَا وَأَمْسَى الْمُلْكُ لِلَّهِ رَبِّ الْعَالَمِينَ اللَّهُمَّ إِنِّي أَسْأَلُكَ خَيْرَ هَذِهِ اللَّيْلَةَ فَتْحَهَا وَنَصْرَهَا وَنُورَهَا وَبَرَكَتَهَا وَهُدَاهَا وَأَعُوذُ بِكَ مِنْ شَرِّ مَا فِيهَا وَشَرِّ مَا بَعْدَهَا

The evening has come to me and the whole universe belongs to Allah who is The Lord of the worlds. O Allah, I ask of you the good of the night, it's success and aid and its nur (celestial light) and barakaat (blessings) and seek hidayat (guidance) and refuge from the evil of this night and the evil that is to come later.

(Abu Dawood)

Alternatively recite this

اللَّهُمَّ بَكَ أَمْسَيْنَا وَبِكَ أَصْبَحْنَا وَبِكَ نَحْيَا وَبِكَ نَمُوتُ وَإِلَيْكَ النُّشُورُ

O Allah we enter the night and the day and live and die with Your Qudrat (strength) and to You do we return.

(Tirmidhi)