Unsuspecting Victim

So, let’s say you had the chance to ensnare an unsuspecting victim teach someone to knit.  I get to do just that next weekend, and I’m totally looking forward to it.  But in the interest of making the process as smooth as possible, I thought I’d poll the collective.  What do you wish you had known when you were learning to knit?  Or what was the best thing you learned as a beginner?  I have a general plan, but I’d love some suggestions!