The key is not denying Him in front of others.. God sees the language of your heart before it's translated into whatever language of the world you speak.. you and God know within you what you believe and that's the main thing. But even if you did mess up and deny Him in front of others.. if you realize it and repent for the mistake God is infinitely forgiving.. just don't die in a state of rejecting God because only then do people go where they choose to go.. to be with or without God forever. But no you don't have to go around hitting people over the head with what you believe.. not all people have the gift of 'preaching'.. some like me are quiet in front of people. The key is that you believe and God knows it.
I'd also like to point out that Jesus hates the captcha…