Over time, I've made sure I give my passengers a 30 second brief just before I ask for departure clearance. It only takes a few seconds to tell them we're about to go, that I'll run the engine up to check T's and P's, roll, check speed and stop on the runway if there's a problem. Similarly, if we get a problem climbing out, we'll do this or that etc.
It seemed a bit odd the first couple of times i did it, but now it's become routine and I feel happier knowing that I've done my best to make sure my passengers (the people relying on ME to do it properly), have a s much information as they need to know what's going on.
Many of us fly with non-aviators. Don't we owe it to them to make sure they are safe and happy in our care?