[dragonwriter]

> Left: Face the noon sun. Lift one arm to point at where it was first seen this morning.

That...fails to be generally accurate pretty badly.

[Groxx]

As a quick example: north vs south hemisphere swaps this.

[dragonwriter]

That's approximately correct, though It think it's most actually “north or south of the subsolar point at noon on the day in question”.

North and South of the tropics will give either consistently right or consistently wrong answers, but within the tropics you'll get different answers on different days.