istikharah
As far as I know and I may not be knowing enough only Allah is, this prayers is not to be done as an absolute (only) means of guidance when proposing an action.
It is a supporting aspect.
Firstly when you have something on mind you would rely on your own instinct and perhaps take guidance from friends, family and others.
You may then want to consider doing something practical like preparing for the task ahead if it is a task or by rationalising the action you want to take eg list all you can think of that is positive and negative or could be about your action; then weigh these up and in order to be divinely guided you then do your prayer.
Some Imam may recommend you do ghusl before the prayer, others wudu, generally the idea is clean yourself, clear your mind and find a quiet place. It is as far as I know ok to light a candle as well and have your qu'ran to hand. Most qu'ran have indexes, you could do your 2 rakat then read what the qu'ran says if any about your area of concern or do kurusiyu and yasn afterwards to put you in the right mind, then you could also do subhanalahi walhamdililahi astagafirulahi laila illa lahu like say 100 times or more and then proceed with asking Allah to guide you to do the right thing or to what is good for you.
The answer is not going to appear like magic, it is just something you do with faith in God and hope he gives you guidance which he almost always does, the main part to remember is that whatever transpires is primarily controlled by you eg if you pray that God should help you to marry your spouse if it is good/right for you then failure does not mean you were guided wrongly but that somewhere something in your actions and so on went wrong. Having said that you may be blessed with divine intervention and guidance, but its all an act of faith not black magic where you see thinigs exploding and imploding before you.
In my culture, nikka is for life, In England, we have serial nikkaist's, if you go to the Central mosque in Lagos asking for a dissolution of your nikka, they will chase you away and ask you to go and seek resolution of your difficulties and not to come and embarass your family here or spoil their good reputation.
With regards to all acts, we must try to instinctively search ourselves before we act, we are not angels we all do wrong, but primarily, as I hear a lot about special prayer, istikharah, I know I was brought up being taught that in all times of uncertainty, need, wants, difficulty and happiness at all times you have the chance, you should make 2 nafilat or more and put your wants, needs, desires and thanks to Allah.
So maybe some of us are missing something out, remembering to make nafilah to thank Allah that he spared our lives today, gave us enough to eat, clothes to wear, food to eat, water to dring, a home to live in and so much we never notice and to sit with our tesbew and do 1000 alhamdillilahi and astagafirulah and allahulaila and recite kursiyu and yasn to thank him for being there all the time.
I pray Almighty Allah helps us all to remember that although there are limitations on relations with ourselves before marriage that there is no rush and that we should always be patient to know each other, remain rational, sensible, have realistic plans and not be so fickle as to imagine Allah will provide without any real action plan, make sensible decisions and above all pray for maturity and not just for the right partner but as I do to pray that Allah remains in my future and not just the present and that he helps me to be of sound mind to be ready to endure anything for my loved one forever.
In many places in the world, it is virtually impossible to get a divorce if you have nikka, you are expected to go home and have a dialogue and then after this to engage family and elders who may well tell you to go talk to each other as you are the ones who chose each other, but basicly to work through the watershed and rough patches and rocky areas which may emerge after the scales of bliss are shed and real living kicks in.
Or maybe, think of the realities before marrying, there is provision for this in hadith, you can sit and write out vows and agreements and expectations, falling foul of this is a reason for dialogue, discussion and resolution first and repeatedly, not just divorce divorce divorce
Allah bless us all with more insight and patience and fortitude to hold our relationships together.