After a friendly battle with Captain Ilima, you can head north to Route 2 on your way to Verdant Cavern.
Go up Route 2 and you will encounter Beauty Krystal. She has a level 9 Cutiefly. You get 288 Pokédollars for winning.
The man standing near the grass will tell you about shaking grass. If you go into the grass, the pokémon will rush toward you.
From there, you can go north up the ramp. If you go southeast from the top of the ramp, you will reach the Hau'oli Cemetery.
In the cemetery, check behind the bottom-left grave to get a Paralyze Heal.
Talk to the guy north of the bottom-left grave to battle Office Worker Jeremy. He has a level 9 Pikipek. You get 360 Pokédollars for winning.
In the upper-right of the cemetery, you can battle Preschooler Malia. She has a level 8 Happiny. You get 96 Pokédollars for winning.
Check behind one of the nearby upper-right graves to get a Big Mushroom.
Check in front of an upper-left grave to get a Super Potion.
In the southeast of the cemetery, you can battle Pokémon Breeder Ikue. She has a level 9 Pikachu. You get 360 Pokédollars for winning.
North of Ikue, follow the path to get TM100 Confide.
Back to Route 2
After you are done in the Cemetery, go back to Route 2. Go north and you will battle Preschooler Dylan, who has a level 8 Drifloon. You get 96 Pokédollars for winning.
Go up the hill until you see a parking lot on the left and a house on the right. If you go southwest here and go through some grass, you find a Heal Ball.
Go back up the hill. There is a motel on the left. Approach the motel, and follow the owner to Big Wave Beach.
Talk to the surfer at the top of the slope down to the beach to battle Surfer Carlton. He has a level 9 Delibird. You get 216 Pokédollars for winning.
Then go down the slope to reach Big Wave Beach.
Big Wave Beach
At the first hut, you can trade BP for items. At the second hut, you can trade BP to teach your pokémon new moves.
Go to the northeast corner of the beach, and the swimmer there will tell you more about Big Wave Beach. You won't be able to Mantine Surf until you have completed the Island Challenge.
Go to the south end of the beach to find Sandy Cave. You will not be able to go anywhere in the cave yet, but be sure to come back when you have a pokémon that can Surf. You can walk around in the entrance of the cave to encounter wild pokémon.
When you try to go back to Route 2, some Team Skull Grunts show up. Talk to them to battle Team Skull Grunt. He has a level 9 Drowzee. You get 288 Pokédollars for winning.
Afterward, the swimmer gives you a Fresh Water.
Go up the slope in the northeast corner of the beach to reach a new area. You can interact with a Pyukumuku there. Go northwest from the Pyukumuku to find a White Herb.
When you are ready, go back to Route 2.
Continue on Route 2
Check behind the truck in the motel parking lot to get a Super Potion.
If you go into one of the motel rooms and talk to the guy sitting at the table, he gives you 2 Nest Balls.
Go east to the house across from the motel and you will find a man looking at the back yard. Talk to him and he will ask you to find his missing Meowth. A girl near the Motel parking lot says she saw one run toward the car. Check the front of the car in the parking lot. Look it in the eye and it will run away. Then go back to the girl near the corner of the parking lot, and walk west of her on the grass to find the Meowth hiding in the corner. Talk to it and Purr at it. The man will give you an X Speed, X Attack, and X Sp. Atk.
Go north and you will battle Gentleman Stanley. He has a level 10 Murkrow. You get 2000 Pokédollars for winning.
Go east from Gentleman Stanley to enter the Berry Fields.
Go east from the entrance and talk to the man near the Delibird. He will give you a berry. If you say Yes when he asks if you want to be a Berry Master, he asks you to bring him a certain type of berry. He will give you another berry if you show him the berry that he asked for.
Check the pile of berries near the man to get some berries.
Go to the right and go into the house. Talk to one of the Delibirds in the bottom-right corner to get a Revive.
Go around the back of the house to get Silver Powder.
Outside, go south into the berry field area. You can talk to the girl to the right for information about berries.
Check on the basket to the right to get a Repel. Go to the bottom-left corner of the area to get a Big Mushroom. Then go around to the top of the tools above where you got the Big Mushroom, and check on the flower pots to get a Paralyze Heal.
Leave the Berry Fields and go north. There will be a cutscene with those mysterious characters from earlier.
After the cutscene, keep going up the path. Go through the grass to the left and find the opening in the fence to the west. Go north along the path to find a Revive next to the wall of the Pokémon Center.
If you jump down the ledge, you will battle Pokémon Breeder Jay. He has a level 10 Rockruff. You get 400 Pokédollars for winning.
If you go to the southern part of the path, you can battle Lass Isabella. She has a level 9 Flabébé. You get 216 Pokédollars for winning.
Behind Lass Isabella, there is a Super Potion.
Route 2 Pokémon Center
Approach the Route 2 Pokémon Center and you will find Hau. He gives you three Revives. He tells you about Roto Loto, which you can use by tapping your Rotom Dex's eyes when they flash. A spinning reel will appear on Rotom's screen. Tap the reel to make it stop spinning, and Rotom will give you a special power. Rotom Powers are kept in your bag.
You can talk to a girl in this Pokémon Center to trade a Spearow for a Hawlucha. Spearow can be found in the grass near this Pokémon Center.
There is also a girl in the Pokémon Center who will pay you if you catch Crabrawler and show her your Pokédex entry of Crabrawler. Crabrawler can be found in piles of berries.
Outside, you can go northeast of the Pokémon Center to find berries under a tree. Check on them to get some berries.
When you are ready, go across from the Pokémon Center and approach Captain Ilima, who is standing outside Verdant Cavern. He will ask if you are ready to start the trial. You won't be able to leave until you complete it. If you are ready, say Yes.