A smartphone app like CoPilot with offline maps is a good choice and their RV app is even better to keep us away from places we shouldn't be. Waze and others like them are social style apps and I guess I'm too old of a dude for that. I don't like them rerouting me to a non-RV style roads and showing my location in relation to another Waze user. I'm sure that's just me!
Also get a truckers atlas and follow your GPS route. I have found doing that at the start of each days drive is a good time for that.