Simply provide the proof.. - Outlaw
Done so already many, many times.
The god of classic christian theism is a logical impossibility. A deity can't be "personal" while also being omniscient.
A creator god is proven to be non-existent by science.
A god who is all powerful and all loving is proven to be non-existent by natural evil.
A god who desires a relationship with humans is proven to be non-existent by 100 000 years of hiddenness.
A god who communicates through sacred texts is proven to be non-existent by the errors in those books.
A god of prophecy is proven to be non-existent by the total lack of fulfilled prophecy.
A god who answers prayers for healing is proven to be non-existent by amputees.
A god who is the absolute standard of morality is proven to be non-existent by the depraved morality of his holy books.
We could go on.
Go ahead and define any "god" you like and it's non-existence can be proven beyond all reasonable doubt.
With the exception of extremists like Perry, theists usually lack the courage to define what they mean by "god".