If you are going on a flight with passengers, the law states that you must give them a safety briefing.
Since I couldn’t find anything that fully met my needs, for a Cessna 172, I put together my own safety briefing. In case anyone else finds it useful, I have published it here.
DISCLAIMER: I am not an expert, or a qualified flight instructor, I am just a PPL. Nothing here is official, and some or all of it might be incorrect! You completely use this at your own risk, and must use your own intelligence and judgement at all times when flying and when speaking to your passengers! If in any doubt, seek the advice of a qualified flight instructor.
You can download my two-page checklist as a PDF or as a Word Document: