When I shoot a load ladder I, too, color code the cartridges with a sharpie and then write the code inside the box lid with sharpie.
When I find a load I like, beside logging it into a notebook, I write it smaller and more neatly in sharpie in the box that contains the ammunition.
This helps with two loads that use the same bullet.
An alcohol wipe cleans it right off, but won’t get lost otherwise.
Even though I really like the little tags that come in the Hornady boxes, they just don’t stay put in the world. Sometimes I just tape these into my notes, they actually stay there.
I had wind steal my paper “map key” once. I could still shoot the color coded load ladder, but had to wait until I got back home to my notebook to what load it was.