I have been studying the Hebridean salutations that go with driving. They range from one finger lifted from the steering wheel, to the full frontal hand at shoulder height, sometimes followed by a cheery thumbs up.
here’s a picture of more work in progress
The most stylish, and the one I have been cultivating, involves a full hand with index finger extended initially, completed with a sideways lilt of the hand. The occasion is on meeting / stopping / giving way to another vehicle at the many passing places on single track roads, but also sometimes just in mere acknowledgement of another driver on the road. Only the locals do that. The foreigners don’t always get it, and certainly don’t get that they should be grateful when I pull over in the tank to allow them to overtake. Local and commercial vans follow that manoeuvre with a double toot on the horn as relief for not having to trail along behind me. My top speed is 55 mph downhill with a fair wind. Average more like 30.