This wikiHow teaches you how to get Rock Smash in Pokémon FireRed. To reach One Island, you need to beat the gym leader on Cinnabar Island. You also need Surf to cross the ocean and reach Ember Spa.
Step
Step 1. Go to One Island
One Island will only be unlocked if you have completed the gym on Cinnabar Island. You can reach this island by boat.
Step 2. Head to the east end of the island on Kindle Road
Step 3. Surf to the north towards the sand beach
Continue north through the tall grass to the sandy area. Keep going north until you see the mouth of the cave.
Step 4. Enter the cave
You will see "Spa Bucket" at the top left of the screen. Follow the north path, then take the stairs before heading east and meeting the man between the two waterfalls.
Step 5. Talk to the guy at the waterfall
He will give you HM06, Rock Smash. Rock Smash will destroy the rocks that stand in your way.
