Assuming that it came up (because I wouldn't bring it up), I usually say "I'm not a believer". This way I didn't say there is or isn't god. I also haven't said that I believe there isn't a god. Which is true; I cannot prove the negative, yadda yadda. I simply say that I am not a believer.
I'll listen to them for a bit, if it goes there, but then I usually try to terminate the discussion. It is rare that I have a mature and intelligent conversation about it anyway.
I do believe that my religion shows in my behavior. Judge me by that.

I don’t try to hide it. Any time that beliefs are brought up I just simply tell I’m not religious. Most will dive deeper to then as to what I believe in and I simply tell them that I am an atheist and believe in science. I have lost people in my life that used to be friends but I feel that is a sacrifice that needed to be made to have more like minded people in my life.

It depends on the situation. When I was younger, I was loud and proud about it. I'm still proud and can be loud but I don't have as much interest in fighting about it, as I used to. "As an Atheist, I ..."

Depending of the type of the believer, I mean type of their character, I'll let them know belief or not. Sometimes hiding in the shadows some times shining like a rockstar it all depends the environment I am in.

Normally, I don't. I try to stay away from magical thinking people as much as possible. For instance, I have friends who much later I found were Jehovah's Witnesses. Now I stay away from them as much as possible because they have to mention Kingdom Hall and talk about how great their religion is in every conversation. In reality, I don't say I'm an atheist unless a religious zealot pisses me off, or I'm very comfortable w/someone who I've found to be logical and sensible. Don't give a crap about these played out holidays anymore.

I usually don't tell them unless they ask. If they do ask I just tell them I am not a believer and I explain why.

I just tell Christians that if they think some Jewish guy died 2000 years ago so asshole like us can spend eternity in paradise they really have thought this thru.

I tend not to say "I'm an atheist," because there's a lot of misguided religious people that think atheism is a religion. I have no problem simply saying I don't believe in god. Sometimes that leads to a disappointed look on their face. Other times it leads to questions. But the best is when they've been speaking to me for an extended amount of time and I drop the atheist thing on them. The look of confusion on their face as their mind tries to understand how someone could be both a good person and an atheist is wonderfully satisfying. But be careful if you try this as their heads do sometimes explode.

I think being upfront is the way to go. Just tell em you are not willing to believe something without evidence.

This is a tough one for me. I try to avoid such conversation if possible, but if I'm pressed i will be honest. By default, our position as atheists is saying that religion is delusional. Its hard to soften that blow, but I honestly don't think it matters what anyone believes. In the end, we all suffer the same fate. If someone is happy with some form of faith, fine. I can respect that as much as my lack of faith. The question is, can they equally respect me.

Honesty is not always the best policy so if I feel the need to be gentle with them I say that I cannot accept the premise offered by most organised religions and cannot believe how stupid it is to kill someone who believes different things.

I say 'We are the majority and are not counted'

I say I was baptized and studied diverse workd religion. But cannot believe in any as they are all devisive.

I am in a tricky situation in this regard. I have a paid gig playing bass in a local Church. I'm Jewish/agnostic rather than an atheist. I seek the divine out in nature but I don't see the divine as being Biblical.

I've been playing in the same Church for almost 15 years. The Priest has become a friend and I think highly of him.

I don't tell people at the Church that I'm a non-believer but I would quickly admit to it if asked.

As far as I am concerned if a person feels free to tell me they are a christian, I don,t get offended, so I have no problem telling them I am an atheist, and if they find that insulting I just say well you told me your belief and heres mine!When people say to me they believe in god, I usually say, Which One? and they look at me dumbfounded and then I say well theres over 3000, of them so which one is yours!

I just tell them "I have no interest in any kind of organized religion." If they have soem sembl;ance of sanity, they then leave me alone. If they persist, i tell them that they are mor eannoying than convincing. That usually does it. After that they not only leave me alone, but dont' bother anyone else i the room either.

If they ask me, I tell them. They like the brainwashing, I like thinking for myself.

I don't believe in any gods, I only believe in things that can be proven. I am not superstitious and I do not think any religions are true.

I just say it no shame here.

If asked I am honest and very proud of it. But I do not walk up and ask someone if they are a christian etc because I find it rude. If it comes up in conversation then ok. Lets talk.

I really only mention it in response to someone pushing their religeon onto me, otherwise live and let live.

my atheist necklace gives it away 100% of the time

I tell them straight out - I am not ashamed of being an Atheist and I remind them that my parents taught me to think for myself, question, read and then make a decision.

I never bring up religion unless someone else brings it up first, or if i'm venting about something and it just happens to slip out. If religion is brought up, most people around me are religious, and they'll ask me if I am, I always respond no. They then want to question why I am not, and tell them it doesn't matter and to just move on.

I just come right out and say.. I am non religious.. I don't need that in my life. It serves no purpose for me. They ask me.. so you don't believe in god? I come back with... which god are you referring to. That usually stops them dead in their tracks.