I used to highlight the route I was going to take on the atlas. So I could just look down at it while driving and see where a turn off to another road was coming up. I still use the highlighted atlas on the seat next to me while driving just to keep the GPS honest.
I found from year to year traveling I never had to highlight the route on the map anymore because it was already there. For me once I find a nice route I take it over and over and over again. I'm too old for surprises now. I like the road I choose to my destination to be RV friendly period.