Reminds me of in the Avengers - SHIELD couldn't navigate the helicarrier, and Nick Fury said "Is the sun setting? Then put it on our left!"
Take an analog watch. Say it is 9am, point the 12pm/midday point of the watch at the horizon directly below the sun, the half way distance between the hour hand and 12pm is the fairly close direction of the pole. So in that case, the 10:30am point would be the pole.
In the northern hemisphere it points South, in Southern hemisphere it points North.
EDIT : The Wikihow article shows it better.
https://www.wikihow.com/Use-an-Analog-Watch-as-a-Compass
It is an old Army/SAS trick for keeping baring without a compass.