Things You'll Need
Instructions
Locate a rock that appears as an obstacle in the main path and walk up to it.
Select a Pokemon that is capable of the "Rock Smash" command and use it on the rock.
Collect the fossil from the remains of the rock. Note that the game randomly generates whether a rock will contain a fossil.
Take the fossil to the museum in Pewter City.
Speak with the scientist inside the museum and he will hatch the fossil.