u/Fullmetalsqrtl

Hey! So basically, I've recently gotten into 3D printing, and I'm having a blast so far. I've gone down the sanding sinkhole, and now I'm curious as to what the stages of sanding look like.

I've created what I think is a good sanding progression in the image provided, but I have a few questions regarding it.

How will I know when it's time to move up a grit number, and do I sand with 120 grit until all layer lines are gone or just mostly gone? And also obviously if this is a good sanding progression.