I am old enough and knowledgeable enough to know how to live my life without anyone to dictate me about it. And/or you can add on, are you trying to insult my intelligent? Are you telling me I do not know how to live my life?

I would be tempted to say, "OH MY GOODNESS! Why on Earth would you ask me such a PERSONAL question? That's something I never discuss with ANYONE.". I would try to look as outraged as possible (which might not be all that difficult at that point in the discussion), and hope that the person gets discouraged and goes away.

Just say you're not interested. if that doesn't work be less polite.

If someone starts sharing their worldview with me I see that as an invitation to start sharing my worldview with them. If I have time and energy I engage them in conversation and try to find something we have in common and build on that.

I have a brain, I use it to learn and find out how to live life accordingly, and earn things I needs and share when I can, instead of pray or let other dictate how I live.

Tell the woman you are working and your employer does not allow non-work related distractions.

Just change the subject and ignore the question.

It's happened to me more than a few times. I just hold up my hand in front of them at arms length (like stopping traffic) and tell them very firmly and very directly "I'm gonna stop you there". No one's ever persisted beyond that. P.S. I live in the bible belt.

I have a good way to shut them up if they will not take a hint. When they tell me that I need to have a close personal relationship with Jesus, I tell them that I am not gay or interested, but if he has an attractive smart sister, I might like to meet her.

"We are all atheists here," I say firmly, with a sweeping gesture to incorporate everyone within sight. Jehovah's Witnesses leave.

"I don't believe in an invisible being that resides somewhere beyond the clouds." That shuts them up.

If you're too busy to talk to them then let them know you're too busy. If you're not then talk a little extra time to destroy their faith. I mean yes it's a little rude but if they started it....

Well my thoughts went out the window. My usual is Oh look at the time mom and I were going to skype. Or another one for me is oh your just in time I needed someone to help me finish my spell. That last one is a more extreme one but has been effective in ridding my doorstep of JW's. The first one is the one I use when having supper with my landlady if she gets preachy who is also a JW funny enough. However she is not pushy but she does get preachy when she is excited.

Now if you are running a booth you could just keep turning the conversation back to whatever the topic is. Or something to the effect of Excuse me mam I am here representing my school's blah blah blah I do not feel comfortable discussing religion as that is not why I am here. I would be happy to sell you some blah or discuss blah with you.

I would just politely tell her the truth. "I used to pray but soon discovered the line was dead." "Why Jesus? There are hundreds of religions being practiced today and hundreds more no longer being practiced. They all claim to be the right religion. They can't all be right."

I might end by bringing up the problem of theodicy: "If god is all-good and all-powerful, why doesn't god simply vanquish evil? Why does he allow innocent children to die horrible deaths due to earthquakes, tornadoes, and hurricanes, etc."

If she didn't walk away after that, then I would.