I don't believe there's to tried and true way to pray for healing. You must become a vessel who God can move through to bring healing.This is a process which God will orchestrate as we pursue Him for first in relationship and then for healing.
The biblical model for healing relates to the Lord's prayer in Matt 6:10, "Your kingdom come.Your will be done on earth as it is in heaven". We need to believe that its always God's will to heal because if we don't we can't pray in faith.
Receiving a word of knowledge regarding a specific healing is the most common way God uses to heal people. This will impart a supernatural gift of faith necessary for healing. Another necessary foundation is a heart of compassion. Both go hand in hand to bring about a healing.
When people were healed in the bible, they seldom prayed for healing, they commanded, declared it or told the afflicted person to perform an action. They spoke things like "in the name of Jesus walk", "arise" or " ears open " ect.