After you find Lillie and Nebby, you can return to Melemele Meadow to explore.
Explore Melemele Meadow
Go into the flowers and go west to find a ramp. Go up the ramp, then go north. At the end, go left down the ledge, then go to the left and up the ramp. Go southwest from there and you will find a Poison Barb to the left of the flowers.
Farther south, you can talk to the woman and she will ask if you will battle her. She is Actor Meredith, and she has a level 12 Oricorio. You get 480 Pokédollars for winning.
Go south from there to find a Poké Finder spot to take pictures from.
Go clockwise from here to find a one-way ledge to jump down.
Go back into the flowers and go southwest to enter Seaward Cave, where you found Nebby earlier.
Go south and you find a Heal Ball next to a rock.
Go right from where you found the Heal Ball and go down some one-way ledges. Jump down each one, and on the way, go north to find an Expert Belt. Keep going down the one-way ledges. At the end, you find a cave exit, but before you go through, go down and follow the path, and go down when the path splits and check on the rock to find a Star Piece. Then go back up and go left to find a Super Potion. Then go up and right from there to get a Never-Melt Ice.
Now go back the way you came and go downward when the path splits. Then go toward the right to reach the cave exit.
You will come out in Kala'e Bay. If it's night, you can talk to the Swimmer and say Yes to see sparkles in the water from Finneon.
Go north from the cave entrance to get a Dive Ball.
Then go south and check on the sparkle and say Yes to open the bottle. Be sure to look for the little sister in Iki Town.
Go back into the cave, then go down and left, and when the path splits, keep going left. Then at the next split, go northeast and you will reach a ramp to the left. Go up the ramp, then go upward to find the hole that you can crawl through to return to Melemele Meadow.
From there, go east to return to Route 3. When you reach Iki Town, you can battle Kahuna Hala.