Using this water bottle carrier bag is super easy. First, adjust the strap to a comfortable length for you, as it can be adjusted from 24 to 48 inches. Then, put your 40oz tumbler or water bottle into the main part of the bag. You can place your phone, keys, ID cards, and bank cards in the detachable pouch or the small pocket with a zipper. When you're in the car, you can directly put the tumbler with the carrier bag into the car cup holder. As for maintenance, you can use a damp cloth to wipe the polyester fabric if it gets dirty. Just be careful not to soak it in water for a long time. Also, remember that the colors in the preview images might be a bit different from the real item because of lighting during the photoshoot or your monitor's display.