This achievement entails completing 3 side quests (blue !)
- Fizzco: The Dirty Secret
- Fizzco: The International Conspiracy
- Fizzco: The Secret Ingredient
The latter are started at a phone booth but I believe the first is started by reading a note at the base.
You need to progress through the story to unlock these missions, the third of which is unlocked sometime during when you are getting the 4th faction to help you (the Latino ninja cheerleaders).