The prayer for guidance (istikhara)
Sahihاللَّهُمَّ إِنِّي أَسْتَخِيرُكَ بِعِلْمِكَ وَأَسْتَقْدِرُكَ بِقُدْرَتِكَ، وَأَسْأَلُكَ مِنْ فَضْلِكَ الْعَظِيمِ، فَإِنَّكَ تَقْدِرُ وَلاَ أَقْدِرُ وَتَعْلَمُ وَلاَ أَعْلَمُ وَأَنْتَ عَلاَّمُ الْغُيُوبِ، اللَّهُمَّ إِنْ كُنْتَ تَعْلَمُ أَنَّ هَذَا الأَمْرَ خَيْرٌ لِي فِي دِينِي وَمَعَاشِي وَعَاقِبَةِ أَمْرِي ـ أَوْ قَالَ عَاجِلِ أَمْرِي وَآجِلِهِ ـ فَاقْدُرْهُ لِي وَيَسِّرْهُ لِي ثُمَّ بَارِكْ لِي فِيهِ، وَإِنْ كُنْتَ تَعْلَمُ أَنَّ هَذَا الأَمْرَ شَرٌّ لِي فِي دِينِي وَمَعَاشِي وَعَاقِبَةِ أَمْرِي ـ أَوْ قَالَ فِي عَاجِلِ أَمْرِي وَآجِلِهِ ـ فَاصْرِفْهُ عَنِّي وَاصْرِفْنِي عَنْهُ، وَاقْدُرْ لِي الْخَيْرَ حَيْثُ كَانَ ثُمَّ أَرْضِنِي بِهِ
O Allah, I ask You to choose for me by Your knowledge, and I ask You for ability by Your power, and I ask You of Your great bounty; for You are able and I am not, You know and I do not, and You are the Knower of the unseen. O Allah, if You know that this matter is good for me in my religion, my livelihood and the outcome of my affairs, then decree it for me, make it easy for me, and bless me in it. And if You know that this matter is bad for me in my religion, my livelihood and the outcome of my affairs, then turn it away from me and turn me away from it, and decree for me the good wherever it may be, then make me content with it.
Note: It is said after praying two rak'ahs that are not obligatory, naming one's need in place of 'this matter'. The narration gives a second wording, 'my affairs now and later', in place of 'the outcome of my affairs'.