Useful tricks to teach;
Pylons are the best landmarks. They can be seen from miles away.
If you’re heading for a bridge over a stream and you’re still going down hill, you haven’t got there yet. If you start going up hill, you’ve missed it.
Assuming you are using a milometer or GPS without a map display;
The squares on the map are 1km. So, for example, if you are on a lane looking for a bridleway on the right and it’s about one and a half squares away, look at your current mileage. If it’s on say, 26.3km, then you can expect the bridleway to appear at around 27.8km, so you can put your head down and concentrate on pedalling up to about 27.5km.
I don’t know exactly how you would put this in to a workshop though.