If you activate a cutscene in mid air and fall and hit the water, you will not start swimming but fall straight to the bottom. There are several ways to do this.
Spell Dive Edit
Discovered by Kazooie
This method uses Din's Fire, Farore's Wind or Nayru's Love
- Get near an edge
- Lure an enemy
- While the enemy is close and ready to hit you, activate a spell
- While activating the spell the enemy should push you off the edge and you will fall
Cucco Dive Edit
Discovered by Dekudude, AKA
- Use a cucco's attack cutscene to dive.
- Get a cucco and attack it until 1 more attack will make it attack you
- Put the cucco in a good position
- Attack it while in mid air, with slingshot/bow sidehop, jumpslash etc.
- The cucco should summon other cuccos to attack and if you did it correctly you will fall through water
Bottle Dive Edit
Discovered by ???
Use hover boots and a bottled item to dive.
- Equip hover boots and a bottled bug/fish
- Get near an edge and dump the bugs/fish
- Back up off the ledge so that Hover boots activate then quickly swing your bottle to catch the bug/fish again
- If you caught it in time the hover boots should deactivate and you will fall through the water