5 years old but some useful lessons: 1. Highlight his hypocrisy by using his own words. 2. Be informed enough to call out his lies/mistakes immediately. 3. Don’t let him change the subject or close down unwelcome questions. 4. Facts. 5. Facts. 6. Facts.
This is well worth your time. Don’t you wish all the Brexiter windbags were given this kind of informed, unrattled questioning?