I dig this at the MMI's Frequently Asked Questions
Preparing for the MMI can be difficult. Since the MMI is akin to speed dating, one might ask oneself, “How can I prepare for this date?”. Familiarity with the format is helpful for settling nervousness. There is no specific knowledge that will helpful to you. You might ask some friends or family members to create scenarios for you based on the examples available on this website. This will at least allow you to get comfortable speaking on a topic for a few minutes and organizing your thoughts on the fly.