Talk to Shamae at the Woodland Stable. She is a little girl. When you talk to her, she will ask if you can make the barrel near her fly like a balloon.
You will need at least two Octo Balloons, which you can gather from killing any type of Octorok. The easiest way to kill them is to sneak up on them when they are chilling above ground and shoot their large heads for a critical hit.
Then take the Octo Balloons and throw them at the barrels. Talk to Shamae and the camera will zoom out showing the floating barrels. As a gift of appreciation, Shamae will give you a rare Star Fragment.