Be sure to also bring the 800 toll free US Hilton phone number, I have found them to be helpful when I am driving and to tired to make it back home in California (Yes, I was pulled over in a parking lot), I have had them check everything within 50-100 miles to see what is most convenient/cheapest points. As others have said, Texas is big, so planning is needed in rural areas; in the cities, it will be easy to call the day you need the room and find a place. But plan early, if you are driving all day, once it gets dark, you get tired really fast and it can be really dark out there. As others, have said you can not book with points at the front desk, but can book yourself from the lobby or the parking lot and then check in. Have fun.