Some time ago I read a post by an inmate who described his use as follows:
He identified the places where he wanted to spend each night (motel, campground, friend, whatever ...). Each morning he'd set that location as his destination on his GPS, then ride wherever and on whatever road appealed to him, letting the GPS auto-recalculate. When the 'arrival time at destination' on the GPS got to the time he wanted to be there (stop riding for the day), then he would follow the GPS route.
At anytime during the day he could find gas/food close to his current location.