Ask him question about sports. Or, ask about his family, his past relationships, his growing up. Look at the art on his walls and ask about it. Look through old photos together. Ask about favorites--movies, vacations, travel destinations, TV shows, etc. Ask follow-up questions. Then, if he doesn't reciprocate asking you, don't wait to be asked. Start sharing your answer.
If you are both quiet, one of you needs to talk. I have a friend that way. She is not a talker. I ask questions and follow up questions, but she doesn't live a very active life, so when she has nothing to say, I share a lot. I go into detail.