I think the hardest part is finding the topic that they are interested. Most people will ramble on about their greatest interest forever. You can't start with "

I think the hardest part is finding the topic that they are interested. Most people will ramble on about their greatest interest forever. You can't start with "How's work?" or "Watch anything good on Netflix lately?". You have to move into something else like "What have you been doing in your free time?" and then follow up on that. Odds are that they will lead you right to their greatest interest almost immediately. I think questions only has to be clarified with positive reinforcement. If they say they like X, your question needs to validate them too. "I'm not familiar with X but that sounds really interesting. What is the coolest thing about X to you?"