Simply tell the story of who Jesus really is, why and how he died, and what he has accomplished through his resurrection. You'll be surprised at how many people just haven't ever put it together. Let your friend see the compassion and humility of this God who became like us. Help them understand that God has chosen to love his wayward people. Be willing to tell your story of Jesus.
Personal experience validates truth in our society.
Yes, Jesus stands firmly as a historical figure and the Scripture is an authentic record, but the story of his transformation in your life is usually far more important to those who inquire. There may well be a time to present the facts and information to back up your faith, but that should come after you have told your personal experience of Jesus. Have the courage to listen and correct. Many times people think they understand Jesus, but from a Scriptural point of view, they have misconceptions. Don't be afraid to really listen to their questions, no matter how scandalous.