Talk to Locals
You're going to meet people along the way that know the area much better than you do. They will guide you to the coolest of places and tip you off on things that you would've otherwise never known. Ask for advice, ideas on what to do next, and the best way to do it. Talk to waitresses, cashiers, rangers at the national parks, and the people that happen to get out of their car for the same photo op. They will change your trip.