Before you start washing the bag, always read the manufacturer’s recommendation regarding how to clean the bag. This can change slightly depending on the design and material of the bag. Most manufacturers recommend submerging the water for a few hours and then wash it with soap. One thing that you should never do with your fishing backpack is to throw it inside a washer or a tumble dryer. Also never use water that is boiling hot to wash the bag. Lukewarm water is enough to get the bag cleaned. You can use a soft brush or sponge as well.