In terms of traveling from one travel nurse assignment to the next, I find it extremely helpful to carry a weekly planner (Week-at-a-glance, Daytimer, Cambridge are some popular brands). There’s lots of room under each day to keep a diary of important things like mileage – which is important to travel nurses.
Beyond that, I like to keep track of each time I fill my gas tank and the odometer reading when I do it - as well as the city I was in and how much I paid for gas. For the sake of my memory, I also jot down any stops I make at memorable places like Mount Rushmore or the Grand Canyon and the cost of meal and lodging along the way.