On my planned layout, operators are required to recreate the real thing faithfully. So the train crews servicing industries along the track, as well as yard crews, have a switchman accompanying the train, to uncouple cars, set and release brakes, connect hoses and (un-) lock or throw switches.
The operator uses a marker to remember the approximate position of the switchman in order to pick him up after the switching is done, by backing up the train until the loco is near the switchman (so he can climb aboard without running along the gravel trackbed). After the switchman is back on the locomotive, the operator removes the marker from the layout and continues to the next industry along the track.
On my layout this marker is a painted figure mounted on a copper plate (one Euro cent).