There is no right or wrong way to convert a prophetic word into a prayer. But there are things that you should verify first.
Is the word Biblically sound?
Does it line up with the expressed will of God as stated in his word?
If it lines up with the Bible then you’re on safe grounds to pray the prayer–provided that your motivation is right. Do you desire what you are asking for to glorify yourself? Or is it to glorify God?
God always checks our motives. Once you are certain that you are operating with the right motivations and that what you are asking for is not in contradiction to the word of God then go boldly before God with your prayer.
Remember that prayer is just a conversation with God. So remind him of the word that he spoke for you. Remind him of his promises. Pray with faith–for without it you will receive nothing from God.
So how can you turn a prophetic word into a prayer?
Identify the key points in the word that you received (those areas that you want to see God move in or bring to pass). Then lift them to God in prayer–not in hesitation but in confidence, as a person who believes he has already received what God has said is to come.
Then ask the Lord for help–help to be unwavering, help to hold on to it in faith, help to clear the path, help to grow in wisdom, help with provision, help with opportunities, help to have the right heart…whatever your need is ask God to give you HELP.
You will run into problems–roadblocks when you try to do it on your own. Because then your faith and your confidence is not in God but in yourself. And how can you bring it to pass when it was not your word that established the matter–it is God’s.
If you want to practice praying the word of God read Deut. 28-30 and claim some of the promises there. Or read the Psalms or Proverbs and claim the blessings of the Lord. Start out slow. Claim one promise a day or a week or even a month…and watch what God will do as you remind him of his word.
Make sure that you have confessed your sins and repented so that your prayers will not be hindered. The Devil is always looking for an excuse to accuse the brethren.