Dua of Istikhara

اللَّهُمَّ إِنِّي أَسْتَخِيرُكَ بِعِلْمِكَ وَأَسْتَقْدِرُكَ بِقُدْرَتِكَ وَأَسْأَلُكَ مِنْ فَضْلِكَ الْعَظِيمِ

Allahumma innee astakheeruka bi 'ilmika, wa astaqdiruka bi qudratika, wa as'aluka min fadlikal-'adheem

O Allah, I seek Your guidance by Your knowledge, and ability by Your power, and I ask You from Your great bounty.

Reference: Sahih al-Bukhari