Hello Bro Dornan
I hope I am grasping the question you are asking.
I talk to a number of ""religious people"" that have difficulty with the existence of God. Although I do not claim to know a best way to discuss proving Him the two most effective ways I have used is.
1. My own personal witness of testimony (people can argue away anything they want but they cannot argue away what you testify of in your own life) They may be able to ignore it or dismiss it but they cannot argue it away as if it hasn't happened.
2. I try to use a bit of reasoning with science through the eyes of the Bible. We know for certain that the moon rotates around the earth, and the earth rotates around the sun, this along with many other combined planets make up what we know as our galaxy. What science suspects but are not absolutly able to prove is that our galaxy rotates around something bigger undefined.
Well then lets consider that the Sun is equatable to Christ (He is the light of the World and in Him is no darkness), the Moon is the Church (Has no light of its own but reflects the Light of the Sun), and the earth is of coarse the World. The other planets are like other dimensions (Angelic realms) that we get glimpses of but do not fully comprehend the fullness of their capacity. All of this then is in its proper place and function by something bigger and much more vast than we can handle but it is absolutly firm in its power, the universe! Our Earth, moon, sun, and galaxy, all are subjet to the will of the universe and it is unalterable. God is in my mind, (in its greatest finite capacity) provable by the universe.
I hope that doesn't sound to strange.

Change a mans mind against his will, he is of the same mind still. ----
Benjamin Franklin.