Instructions
Stand in the courtyard in front of the red door; press "B" to display your map. Observe the layout of the six statues in the courtyard and make note of the directions they face. Imagine a line extending from each statue in the direction it faces to discover the key shape. The statues form two side-by-side diamonds that share a central vertex.
Approach the red door and tap it with your stylus to bring up a focused view of the door's surface.
Use your stylus to trace the pattern from the statues onto the door. When you have completed the pattern, the door will unlock, allowing you to enter the Ocean Sanctuary and obtain the note from Carben.