I started with getting a solid 100 yard zero, and remembering everything I did behind the rifle to make those shots...

and parallax use to kick my ass cause I do occasionally get a little complacent.

Your cold bore shot/first shot of the day will let you know if your doing something wrong with the idea that your zero doesn't change.
Figuring that out... then you move out further.

I'm only out to 400 or 500 yards for solid DOPE right now... anything further... I'm SWAG'ng it