Not to insult but if you can't create slides for pre-flight briefings for anything, you're not qualified to teach it.
Like bose-x said, get a textbook and make the slides yourself. It will require you to get even more familiar with the principles of multi engine flight and if you don't learn a thing or two after making the slides, you didn't do them properly! Put some time and effort into making them. I've seen some very poorly designed presentations with some info that's just completely wrong. Don't be part of the lack-of-good-instruction problem.
[/rant]