One thing you might want to teach guests on your boat is how to tie a fender to your boat.
Often, when you need others to tie fenders to your boat (instead of being able to take the time yourself), it’s when it’s urgent. Like the time we had a boat slam into the side of us at 3am in Great Harbor, Jost Van Dkye.
While it’s probably ok to tie any old knot in an emergency, if you have to readjust the height (which we did), it’s best to have used a round turn and two half hitches.
Clove hitches are ok in a hurry but I would replace them with round tuns with two half hitches to ensure you don’t lose your fenders.
And what if you or your guests like to call them bumpers? I have had to give up on getting my crew to call them fenders. In protest at my funky sailing language my significant other and my kids now call them bumpers on purpose …
A round turn with two half hitches can be practiced any where and is a pretty simple knot to learn … You can watch a video of how to tie one or check the image carefully.