This page explains the next things you can do if you unlocked the Nintendo Gallery and upgraded your Picto Box right after you got the Deku Leaf in the Forest Haven.

New Things to do on Windfall
The next time you return to Windfall after you get the Deku Leaf in the Forest Haven, there are several optional things that you can do while you are here.
If you haven't learned the Song of Passing, go to the dancing man at the gravestone in the northwest part of the island, talk to him, then use your Wind Waker in front of him to play a few notes, and he will teach you the song.
If you have a Forest Firefly and you haven't upgraded your Picto Box to the Deluxe Picto Box, use the Song of Passing to turn it to daytime, then give Lenzo the firefly to get the upgraded Picto Box.
If you want to start taking pictures for the Nintendo Gallery right away, you should leave one slot free, because there are some bonus items you can get on Windfall by taking certain pictures. These will be explained below.
If you haven't played the battleship game across from Miss Marie's place yet, you can play it now.
If you have 20 or 50 joy pendants, give them to Miss Marie. For 20, she gives you the Cabana Deed. This item will be required to complete the game, but you can wait until later if you don't have enough Joy Pendants. For an extra 30, she gives you the Hero's Charm, which is a mask that you can equip on the Quest Status screen. Wearing the mask allows you to see the life meters of your enemies.
Go to Zunari's shop (the guy who sold you the sail), and go to the counter on the left side. Talk to him a couple of times at the left counter, and agree to help him get more merchandise. He gives you the Town Flower.
Go to the potion shop and talk to the lady standing outside by the sign, then take her picture, making sure that her whole body is in the picture. Then show her the picture and she will give you treasure chart #33.
Talk to the two gossiping ladies a couple of times until they mention Lenzo and his "mystery woman". Go into the battleship shop, up the stairs, through the door, and into the ferris wheel car around the corner. Face Lenzo's shop and change the wind direction to that direction (west). Use your deku leaf to glide into the little balcony. Go through the door. The chest on the left contains treasure chart #29, and the chest on the right contains 50 rupees. Crawl into the hole between the chests. When you reach the end, you will be near the stairs that lead up to the photo gallery. Go to the left, and take a picture of Lenzo and the woman together. It doesn't matter if he spots you first.
Go back to those gossiping ladies and show them the pictograph of Lenzo and the woman. They'll give you treasure chart #24.
If you haven't learned the Song of Passing, go to the dancing man at the gravestone in the northwest part of the island, talk to him, then use your Wind Waker in front of him, and he will teach you the song. Then go up the ladder to the left of the arch that is to the left of Miss Marie's school. Use the Wind Waker to switch to night time and take a look at the moon. If it's full, take a picture of it (with no clouds in front). If it's not full, keep playing the Song of Passing until it is, then take its picture. Go back to daytime, talk to the grumpy looking guy on the stairs (in the east part of the island near the potion shop). Keep talking to him until he tells you to show him a picture, and show him the full moon picture. He'll give you treasure chart #31.
If you haven't gone to the Forbidden Forest dungeon yet, and you want to have some figurines made, only fill two slots of your Picto Box with pictures of people from town, because you will need a third slot free for later. See the Nintendo Gallery Figurine Checklist for the full list of people on Windfall you can take pictures of, along with advice on taking pictures that the Nintendo Gallery guy will accept.
Optional Pictographs
If you have a treasure chart for Dragon Roost, you might not want to use it because it leads to 200 rupees, and if you're playing the GameCube version or Switch 2 GameCube version, 200 rupees is all that you can carry, so you should only get this if you have no rupees. In the Wii U version you can carry 500 rupees.
If you haven't taken a picture of Valoo, you might want to return to Dragon Roost Island. Valoo is on top of the island. Just go around to the north side of the island, get close enough so you can see more than just Valoo's shadow, but far enough from him that you can see his head, and take a picture.
From there, go south, and when you pass Bomb Island, which is one square north of Forest Haven, talk to the merchant there, then give him the Town Flower (from your Delivery Bag) and agree to accept the trade. Keep trading with him until he gives you an Exotic Flower, although he might not give you that type yet.
Get Figurines Made
Back in the Forest Haven, return to the Nintendo Gallery to have figurines made from any pictographs you took. Talk to the guy behind the counter, then use your Picto Box in front of him, and select a picture. It takes a day for each figurine, but all you have to do is go outside and play the Song of Passing twice, then go back in and talk to the figurine maker, and it will be ready for you. You can give him a new pictograph as soon as you have talked to him.
Feel free to take pictures of the guy behind the counter, and the guy who went into the gallery when you first opened it, who is carrying a bag with an 8-bit Octorok on it. If you can't find him, he sometimes goes to different rooms in the gallery, so check the rooms until you find him.
Use the Treasure Chart
You might now have a treasure chart for the Forest Haven (#31). If so, you should go get the treasure now, because it is a Piece of Heart. To find it, get in your boat and press up on the directional pad to open up your sea chart, then press Y to switch to your treasure charts. Press R to switch to the right side of the screen, then press right and/or left on the D-stick to go to chart 31, and press A to open it. If the left side of the screen isn't showing Forest Haven, press L, then move the cursor to the square that has Forest Haven in it. When you're in the right area, your boat will be displayed on the blue chart. If your map is not open and you're sailing around, sometimes you will see a bright arrow pointing to the sea when you're facing the area the treasure is buried. That arrow disappears before you get very close, so the arrow just helps you go to the right place, but it is no help in finding the exact location of the treasure. Instead, just maneuver your boat and keep checking your treasure chart until you're located almost on top of the X on the treasure chart display. Try to be to one side of the X, then use the grappling hook, press left or right on the D-stick if you need to change which side it's on, and press the grappling hook button to get the treasure.
Get Figurines of the Koroks
It's best to get figurines of the Koroks now, because later in the game they will each be on a different island. There are 8 Koroks to get pictographs of now.
You'll need to go into the Forest Haven several times. Be sure to use your Deku Leaf to stun the Boko Babas along the way. It's easier than trying to do a jump attack to stun them.
There are three Koroks hanging around inside the Forest Haven on the ground floor near the Deku Tree. One of them is on the grass close to the lilypad in front of the Deku Tree. There is another nearby, looking at a Baba Bud. Another one floats around the Deku Tree, landing on the ground after a short time, so take the pictograph when it lands. Get the figurines of the first three, then come back.
There is another Korok on the first branch of the tree that you reach when you take the baba buds up. Take its picture, then continue going up. When you get to the branch where the deku leaf was, float down to the platform with the grass in the shape of an arrow. There is a Korok here, so take its picture. Then go outside, and there is a Korok here on the platform, so take its picture too. Change the wind direction to north so you can glide to the figurine gallery with the Deku Leaf. Get the figurines made, then return to the ledge outside where you took the third picture.
From the ledge, change the wind direction to southwest. In that direction, you can see a small island with a cyclone circling it that you need to float down to in order to find another Korok. After you have taken the picture of the Korok on this island, change the wind direction to northeast (not north, because the Nintendo Gallery is too far to reach from this island), then wait for the cyclone to be almost between you and the Forest Haven, then hop off the edge and use your Deku Leaf to float onto the cyclone. Then you can float onto the lower ledge that sticks out of the Forest Haven. From the Forest Haven, go back to the gallery and get the figurine made.
Go to the Forbidden Forest
Now you should continue with the story.
Back inside the Forest Haven, go back up to that branch where you got the deku leaf. Face the direction of that ledge that has the grass in the shape of an arrow on it, jump off the branch, and glide down to it. Cut the grass there to replenish your magic, and go out.
Cut any grass out here if you still need magic. The Forbidden Forest is too far to reach from this ledge, so face the little island with the mini-cyclone circling it, and change the wind direction to SW. Before you jump, try to wait until that cyclone is between you and the island so that it moves out of the way before you get there, since you don't want to get caught in it.
When you land on the little island, cut grass to replenish magic again, then face the Forbidden Forest and change the wind direction to NW. Before you jump, wait for the cyclone to be to your right. When you see it there, jump forward so you're to the left of it, and start gliding. If you do it correctly, you'll get caught in the updraft. If not, you will lose a quarter heart and end up back on the little island. Wait for the right moment, then jump into the cyclone. As you approach the Forbidden Forest there will be some peahats. If they get too near, tap the deku leaf button to bounce the leaf and get rid of the monsters.
Land at the Forbidden Forest entrance, and cut grass to replenish magic. If the peahats approach, first use your grappling hook on them to get golden feathers, then use your Deku Leaf on them while standing on the ground to blow a gust of wind and make them fall. If they fall onto your platform, you can defeat them with your sword. Then go into the Forbidden Forest.