You could always just say "no", but that's frowned upon.

I generally ask them which 'god' do they mean... if I really want to piss them off

Say that you want to make a sacrificial burnt offering (..a goat, lets say...) to Zeus (they can't argue WHICH god you vow to). If they don't go for that, demand that god appear in person to hear your vow. No, maybe they won't have a sense of humor...When they ask if you swear to tell the truth, just say, "yeah, whatever..."

You are in the US, so how can it be constitutional having to use a formula that involves god? Most countries I know have legal provisions for people to do some formal act of telling the truth where doing it on a holy book (could be the Bible or the Qran etc) is an option, but not a requirement.

Wasn't ever thinking of lying? Lol!That's stupid and makes things more complicated than they need to be. Just was curious about what y'alls take on it was,thanks for the feedback

Tell the truth. Let them know you'll swear on the constitution. OR inform ahead of time that you don't believe in god.

I would respond, "I tell the truth without any outside help."

You are are there swearing the truth, why start out with a lie. I think "so help me god" should be replaced with "under penalty of perjury".

You say which one? It gets funny after that. If you want to be one that fits in with the crowd then leave the funny stuff at home.

What choice do you have? To lie? If you're secure enough in your non-belief then none of it should really bother you.

We can't force other people to see things the way we do. In fact, we shouldn't want to. That would be rather selfish of us.