Salat al-istikhara is two rakat. Prophet Mohammad said when one of you is about to decide something, let him or her offer two rakat. Then, he or she should say: “Allahumma, I ask for Your guidance with Your thorough knowledge. I ask You to help me with Your might. I ask for Your favors. Allahumma, You know while I don’t. My Lord, You can, while I can’t. Rabbi, You know the unknown and the unseen. allahumma, If You know about this issue, naming it; for example, he could say: “My marriage to (….), or my travel to (….), or buying (…..) etc. Allahumma, if this decision is good for me, in my religion, my worldly life and my hereafter, make it easy for me, bless it for me. If You know that it is bad for me,  in my life, my religion or my hereafter, discourage me from taking such a decision.”