Things You'll Need
Instructions
Play through the game until you gain control of the airship called the Highwind.
Go to the Chocobo Ranch near the town called Kalm and rent out three stables. Buy some greens from Choco Bill and then equip the "chocobo lure" materia on one of your characters.
Walk around on the chocobo tracks near the amusement park called Gold Saucer until your party is attacked by a chocobo accompanied by two other monsters. Use the greens on the chocobo to keep it occupied and then kill the other two creatures. Send the chocobo back to your stables after the battle.
Travel to the city of Mideel and repeat this process on the nearby chocobo tracks.
Take the airship to the town called Bone Village and fight in random battles there until you are attacked by a Vlakarados monster. Use the "steal" materia to steal an item called a "carob nut" from the creature.
Return to the Chocobo Ranch and breed your two chocobos together. When you are prompted to use an item, choose to use the "carob nut" you stole earlier. When the breeding is finished you should have a green chocobo.
Take the green chocobo to the large island on the western edge of the world map where the city called Wutai is located. Ride the chocobo over the mountains that you can't walk over and where the airship can't land. Go inside the cave on the other side of the mountains and take the mime materia found inside.