My friend doesn't have a relationship with Jesus Christ, what do I say to him or her?

The most important thing you can do to lead your friends to Christ is to act out what you believe. People will come to know God by the way we act and treat other people. The second thing you can do is is share your testimony. Your testimony is the story of what God did in your life and what He is currently doing.
And lastly, you need to invite them to church. Our Wednesday night services are designed for those who don't know Jesus and we give many opportunities for them to respond and make a decision to follow Him.

Here are some key verses you can share with your friends:

John 3:16 "For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life."

Romans 3:23 "All have sinned and fall short of the glory of God."

Romans 6:23 "For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord."

John 14:6 "Jesus answered, "I am the way and the truth and the life. No one comes to the Father except through me."