What's the best way for a Christian to witness to Atheists, or people of any other faith?

I’m a Christian minister, and I’m looking for advice on how best to present the Christian faith to people who are opposed to it, or indifferent to it. Obviously, as a Christian, I believe it’s important to share what I believe to be the best thing to happen to me in my life, because I don’t want to withhold something that was so good for me, from other people who might need it. I have noticed, though, that some people tend to shut out anything I have to say, when it relates to certain “buzzwords”. How do I share my faith, in such a manner that the average Atheist, Muslim, Hindu, Buddhist, etc., will be interested in hearing what I have to say, and give it some serious consideration? I’m open to any and all sincere suggestions.