1, sound the crash alarm to ensure you have everyone's attention.
2, close the circuit to all inbound traffic and divert local traffic to their alternates.
3, grab the bull horn off the Ops desk and call for QUIET in the most commanding voice you can muster.
4, drag the offending instructor by his ears out of the briefing room and then frogmarch him outside to where the club aircraft are parked, motioning the assembled throng of onlookers (including the offended student) to follow you.
5, using the tow rope kept in the back of the firetruck, tie the instructor to the nearest prop with his arms out in a sacrificial pose.
6, grab a couple of jars of Avgas off the samples shelf in the oil store and liberally drench the instructor
7, nonchantly taking a book of matches out of your pocket, make eye contact with the instructor and ask him: "So, this knots per hour malarky I heard you coming out with just now, you sure about that... hmm?"
8, without breaking eye contact, remove a match from the book and take a step forward, and say: "I'll say that again, sonny... are you sure that knots per hour was what you meant to say?"
By now, it's likely the instructor will be pleading for forgiveness and swearing by Icarus Almighty that he'll never make the same mistake again. Too late.
10, turn around so your back is to the instructor and you're facing the crowd that will have undoubtedly amassed. Strike the match and without a backwards glance toss it over your shoulder, and say: "We take instructing VERY seriously round here... now, who'd like to explain the quadrilateral rule to me?"
(Sorry, Foxmoth, couldn't resist
)