I keep an equipment bag in my boat that has gore-tex pants and jacket, a towel, bug spray, sunscreen, extra sunglasses and an extra hat. I always keep an extra jacket, sweatshirt, sweatpants and hoodie in my truck. I usually throw an extra pair of shoes and socks in the truck depending on if it's hot or cold out. Boots if it's cold, sandals if it's hot.
Dave