It’s easy. You’ve been doing it wrong.
Ask these questions:
1. Are you a serious atheist?
2. Are you a seeker of truth?
3. Are you open minded?
4. Can I draw you a picture of a circle. A very large circle (a visual aid is good).
5. Imagine the circle is filled with all knowledge.
6. How much of this knowledge does a circle of your knowledge represent?
7. Ask “is it possible that God could live outside your circle of knowledge?”
8. Thank them for being open minded.
9. Convince them that they are actually agnostic.
10. Remind them that they are a seeker of truth.
11. Suggest that there could in fact be a God.
12. Suggest that they find out why so many other people believe in God.
13. Point them to Psalm 14:1 – call them a fool.
14. Give them a book. Preferably the book from this video.
What could possibly not satisfy the questioning intellect from that approach?