Spend time with people regularly.  
Truly care.  Be a good listener.  Do that and you’ll find that trust is built and that real stories get shared.  You can share your questions, hurts, and hopes with them, and likewise they with you.  Most people are dying for an open and trusting relationship.  

In the course of talking about real issues in life, you’ll find yourself talking about Jesus.  This isn’t pushy proselytizing, it’s just talking about life as you know it.  If they don’t like the Jesus topic, social etiquette is to drop the matter.  If they are open, you’ll quickly learn how the good news of Jesus is a help to their real-life issues, and you’ll get to share that with them.

If faith conversations are happening regularly on the fly, then you might as well schedule them with intentional regularity.  A little structure goes a long way when someone wants to specifically explore his or her life’s purpose, in Jesus, with you.

Invite as many people from your circle as you can – you’ll find that everyone has a lot to offer each other (instead of relying just on you) and that spiritual momentum is often caught in community more than taught on the side.