Optional: Machamp Detour

Sandy Cave: First off, fly to Big Wave Beach on Melemele Island and head to the southernmost part to find the entrance to Sandy Cave. Once inside, make your way north-east to the island in the middle. After that, head north towards a large block. Call out Machamp and push this block north into the gap right above it. Doing this will reveal TM24 Thunderbolt! Grab it and then head out of the cave.

Lush Jungle: Now, make your way to the east side of Lush Jungle, where those Sudowoodo used to hang out. Look for a giant block on the far east side. You'll want to approach it from the north and push it south into the gap. Hop over the block and exit to the east. You'll find yourself in a small cavern. Continue east until you see another giant block. Push this one east until it's just below a gap in the ceiling, but don't push it any further. Then, position yourself to its south and push it north into that gap. Right below where the block was, you'll find a Hyper Potion. Also, check the rocks nearby to snag a hidden Rare Candy. Finally, exit north from this area to find yourself on a ledge overlooking Route 8. In the top-right corner of this ledge, you'll get TM53 Energy Ball.

Diglett's Tunnel: Head to the westernmost part of Diglett's Tunnel, ideally coming from Route 9. You'll need to navigate a tight path south-west, then run past a Pokémon that's burrowing in a circle. At the end of this path, you'll see a big block to your left. Get Machamp to push it west into the gap right next to it. This opens up a path to the northern part of Konikoni City. Go west and up the slope. Look for an outcrop to the right of the slope to find a hidden Big Pearl. Near the lighthouse, you can also pick up TM61 Will-O-Wisp and Totem Sticker #050.