Paper Mario: The Origami King is much like past entries in the series where some puzzles are easy and others are less obvious as to how to solve them. One of these spawns during the Picnic Road area while you're on the hunt for the Shell Stones. Near the middle of the main area, you'll notice a small pond with an origami swan swimming in it. Since most of the elements in this game are there for a reason, you're probably trying to figure out how to reach the swan because you can't swim. There is a way to reach the swan and this guide will tell you what you need to do.
How to reach the origami swan
The origami swan found in Picnic Road in Paper Mario: The Origami King will continually swim left and right in this small pond, never getting close enough to the edges of where you can do anything. As a result, you need to find a way to get closer to it.
To start, head to the right side of the pond and you'll notice an already used block right there. Move to step on the block and all of a sudden another question mark block will appear to the left of it. This gives you the cue to pull out your hammer and hit the new box and step onto it, which then leads to another box.
What you need to do now is keep doing this until you've gathered a few blocks here where you can get right next to the swan. Now wait for the swan to swim right next to the leftmost block you can climb on and hit it with your hammer. Eventually one of the many toads will turn into an origami swan and now he is free.