Sail

To be quite honest, this didn't have to be a pick-up item as it only has one function. The sail is of course necessary to move about with your boat, so you have to equip it to one of your three item buttons whenever you're on the ocean. The only reason it's a separate item is because you have to find it before you can take the boat.

To get it, head to the north of Windfall Island to find Zunari, the trader and buy it from him for 80 rupees.

To control the direction you're sailing in, move the left analog stick. The wind direction determines the speed at which you're going. To jump, press R. If you move the stick after you land from a jump, you will perform a quick turn.