Hand signals
In the 1950s in SA we had to use hand signals, one for RH turn and one for LH turn or stop (cars didn’t have brake lights or turning indicators on the back, only driving lights). It was really annoying when raining heavily as rain would get in the car through the open drivers window, and it was illegal to drive with the window up. Some trucks had artificial human arms built on the outside of the drivers door, operable from the inside with the windows up. What luxury!!