Hello Friend
The Lord loves you very very much. All you have to do is talk to him, like you would a good friend. No special "sinner's prayer" formula. Just let him know you are sorry and that you need his son.
Father,
I ask right now that you make yourself real to my friend here. I pray Father that you remove any false ideas this person has had about you that the media, other Christians, or anyone else has presented. Father, we know that your love is perfect and exceeds anything and bypasses all the false representations of you.
I ask Lord that this person will have a keen sense of how much they are loved. I ask Lord that you will send someone to minister to this person. This person when coming to you, is clean. They are on an even playing field. No one is "more righteous" than the other.
Father, remove all guilt from this person's life and place this person either in a church home or perhaps a small group.
In Jesus name
Amen