First Define your God.
secondly explain your God.(optional)
thirdly provide evidence/proof of your God.
Example
Abrahamic God:
Omnipotent(all powerful)
Omniscient(all knowing)
Omnibenevolent(all loving)
Define:
He created everything in 7 days. The universe is 6000-10,000 years old. etc…
Proof:
LooL you got me. Which is a pretty good reason why I dont believe in the Abrahamic God. But I dont claim to be omniscient. perhaps someone will beleive in the abrahamic God and have evidence for his/her existence.
edit/ if your God is already self-evident, provide proof for the attributes.
Atheist Quotes 