Forest Haven (F6)

Wind Waker Dive to Forest Haven Entrance

Discovered by Cerpin

Climb up the first few platforms and then stand near the ledge by the wall with the tree branch growing out of the side. Move towards the ledge, and just before you fall, pull out the windwaker to windwaker dive. Wait a second, and then exit out of the conducting menu. Swim over under the entrance to the Deku Tree's chamber and wait to surface. When you do, you should surface above ground and in the loading zone. Though this is a bit slower than the below method, it is used more often because it is easier.

Diving from Beedle's Shop Ship

Discovered by Razor7581

Instead of climbing the platforms as done above, you can jump onto the bags on the side of Beatle's Shop Ship and windwaker dive from there. Since Beatle is stationed on the left of the platform where the opening cutscene occurs, this makes using the ship a bit faster than the above method. Similarly to the previous method, just walk towards the edge of one of the bags and pull out the windwaker right before you fall to windwaker dive. However, even though this method is faster, it is normally only used in segmented runs as it is more difficult.

Jumpslash to Makar

Instead of having to grapple to the pole above Makar's waterfall, adjusting you height, and then swinging in, you can simply use a late-timed jumpslash after jumping from the ledge across from the waterfall.