Lot of good answers here already. Fisherman like th big coolers to sit on but your cooler doesn’t need to be that big. Some fishing boards come with cooler mounts and offer coolers w rod holders on sides. Ice mule makes a dry bag/ insulated cooler that has places to clip down to deck bungee and can easily fit under the bungee, my favorite. AO Coolers makes a SUP Suction cup mount cooler that works well. Suction cups can slide around on a wet board a little but it as well as some other coolers can also be clipped down w S-type biner clips to deck bungee, they are great for securing items to the deck bungee. Another option is to put cans in Yeti style Stainless Steel Cozi-s and place in dry bag, my choice for a sunset social paddle where 2-3 beers is enough. Heavy loads shouldn’t be placed up front on your board if you have space behind you. Also, you can freeze water in a Nalgene bottle as an ice pack, if extra water is needed you just let it melt in sun. A Hydro flask Thermos is best if you just need cold water.