Circular polarizer help

[Jix]

I use the white strip as an indicator of where to start by turning it towards the sun.
Then I adjust by rotating the outer ring until reflections are gone or colour/contrast is to my satisfaction, viewing through the viewfinder.

is using a pencil to mark to my settings ok? cos this is what i do.

 

[AncientMariner]

is using a pencil to mark to my settings ok? cos this is what i do.

Anything is ok as long as it works for you.
Personally, I rather adjust to what I like looking through the viewfinder.