After the interview presentation, take a random object out of your pocket or your backpack. The more random, the better. You cannot use a cellphone, or keys (but you can use a unique keychain). Come up with 10 open-ended questions for that object. That means, the answer cannot be one-word (yes, no, maybe, etc.). The only way you can use a close-ended question is if it leads to an open-ended question. The close-ended questions will not count toward your minimum requirement of 10 questions.