On the off chance that denial is ineffective, once in a while (immediately after listening to NPR), I blurt out my expectations for teenage behavior: "DO NOT EVER TRY HEROIN! IT CAN KILL YOU THE VERY FIRST TIME!"
I'm often struck by the opening sentence of a novel or short story. It can draw me in and set expectations for what's to come. This isn't always true, of course, but a story's first line is the author's opening salvo.