I’ve had several Christians ask me this:
"What are you going to tell god after you die? What are you going to tell him before he sends you to Hell? "
I mostly just tell the little Christians that hypothetically if their god were real, it can erase me from existence because I didn’t ask to exist nor do I care. Mythologically, I think the Lake of Fire is supposed to wipe out non followers from existence anyway, if I’m not mistaken.
What do you say when asked this question?
Depends on which god it is! If it is Azathoth, I’m just going to run.
I’ll be horrified if it’s Sheogorath 
Hi 
Filler for the necessary requirement to post
I don’t believe any deity exists, and there is no objective evidence I will survive my own physical death in any meaningful way.
I’ve never been asked this question.
I usually respond by saying something along the lines of,
If there is a god, I’m most certain it won’t be any god man imagined. At which point I’ll say “what’s up fuck nuts?”
I get mixed responses as you might expect.
“Which God?”
“The God of the Bible.” (I have to pin this down first because I don’t want them sliding into some amorphous being that exists beyond time and space who is all loving.) Step One: Exactly which god are we discussing?
Oh! The god of Abraham?
“YES!”
I would ask him why he is so proud of being jealous petty, unjust, unforgiving, vindictive, bloodthirsty bigoted, misogynistic, homophobic, racist, infanticidal, genocidal, filicidal, pestilential, megalomaniacal, sadomasochistic, capriciously and a malevolent bully.
But I would have to put that on a card and carry it around to remember it all. The short version is “Why is your god such a fucking ass?” He kills kids for calling a man 'baldy." He condones slavery. He tortures Job. He floods the world, killing all flesh, saves animals, and then demands they be sacrificed. If he worked for any major company in the world today, he would be fired for incompetence. The Bible is a record of God’s failures.
SORRY: So I would ask him: “Why in the fuck didn’t you do it right the first time?”
I forgot to respond directly to the question. Seriously though. If is was an all powerful bla bla bnla… what in the hell is all this failure about. The failure is God’s not mankind’s. After all, he is the one with perfect knowledge and a plan.
Easy. If it is the god of the bible to which they are referring, my response to them would be, “I would say absolutely NOTHING. I shouldn’t have to say anything. Your god should ALREADY KNOW exactly why I am there and what I am thinking/feeling.”
No. That’s Santa Claus. Do you think God and Santa share the same Naughty and Nice list? You know, doesn’t that make the Easter Bunny better than both of them. The Easter Bunny passes out those dang chocolate eggs to everyone. No mention of naughty or nice! Unconditional Chocloate Love. I think the Easter Bunny makes a better God than God or Santa. He is a lot less judgmental, and has never said a word about sexual partners or positions or masturbation. I vote for the Easter Bunny for God.
Why, he’s blind, remember?
I tell people (if they are willing to listen, as opposed to preaching) that God has chosen to be hidden from human view (divine hiddeness?), so it’s reasonable that God wants us to act as if He doesn’t exist.
So, if God consigns my soul to the lake of fire, than He is unreasonable . . . and if God is unreasonable, then we’re all screwed with a pinecone anyway, so debating this question accomplishes nothing.
What would I tell god?.. Hmmm… 
… Ah-ha! I know… “Thanks for the fish!”
Well the first thing I would do is pinch her/him and then I would pinch myself and finally I would say, " wow so you’re real. Anyway no harm no foul right." Of course I would hope not to go down laughing
Well, lets take the hypothetical and add that we’re coming before the Christian god.
I’d tell him he did a piss poor job at showing me any proof of his existance.
And that the claims of his minions and the writings about him were nonsensical.