But in your hearts revere Christ as Lord. Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect,  keeping a clear conscience, so that those who speak maliciously against your good behavior in Christ may be ashamed of their slander.
(1 Peter 3:15-16)

No one wants to feel lectured or judged when you present your faith to them.  In fact, that's a great way to turn someone in the opposite direction.  Be soft with your words, be consistent with your behavior, and let God open their minds and hearts to accept His word.