Where should you start when sharing the Gospel?

David L. Turner:

In evangelism and apologetics the Christian should not attempt to prove the existence of God to the unbeliever.  The unbeliever, if he is honest with himself, knows this already.  The Christian should proclaim the gospel, God’s appointed dynamic for turning the lost to himself.

In an article, “Cornelius Van Till and Romans 1:18-21: A Study in Presuppositional Apologetics,” GTJ 2:1 (Spr 81).