It is often said that you cannot prove God does not exist, because you cannot prove a negative. Since we know God does not exist, because the idea is insane, we certainly ought to believe we can prove God does not exist. In fact the solution to this conundrum is simple, once you know how.
We prove God does not exist, by showing what God is.
This approach stems from the nature of language, which generates ideas that often prove fanciful, but are prompted by experience. Proving things do not exist is a routine feature of science, only science is not presented in this negative light. Nonetheless, when science does prove certain things it is liable to disprove ideas that had previously existed.
The idea of God is undoubtedly the most important idea in existence in our world, and the associated knowledge, religion, is likewise of supreme importance. It is still complete and utter rot, but the typical atheistic line dismissing religion as rot, gets us nowhere. If instead we recognise the eternal importance of religion, and ask why ? Then we begin to move in the direction of finding an answer, and thus proving God does not exist, by showing what God is. That is to say, by discovering what it is in reality that does exist, that is as important to us as God is said to be, by those who support this idea.