If you take time with the Bible, starting with the New Testament, then perhaps Isaiah, Proverbs, Psalm, you'll have a working knowledge of effective prayer.
One big factor is no unforgiveness in your heart. Love for your fellow man that compels you to pray for someone is what is needed. Take some time and do it. Prayer is always effective if done by our Savior's rules. Prayer does not have to be elaborate, but it must be from the heart. It Is the way God gave us to talk to Him, just as the Bible is His way of talking to us. Have a blessed day. Praise the Lord!
Remember Jesus Loves You
Prayer of Salvation
Lord Jesus, I thank you for what you did on the cross for me. Your blood washed away all my sins, by your stripes I was healed, your death and resurrection brought me salvation. Please forgive my sins, and come into my heart as my personal Savior.