Throughout the game you will be able to unlock special clothing in different ways, following the description of the clothing is how to unlock it.
Click any pictures to enlarge
How to Unlock: Complete the mission “Three Leaf Clover” for Packie McReary
Liberty Sanitation Department Outfit
How to Unlock: Complete the mission “Taking In the Trash” for Ray Boccino
Albanian Motorcycle Gang Jacket
How to Unlock: Complete the mission “I Need Your Clothes, Your Boots, and Your Motorcycle” for Gerry McReary
Happiness is…Land Sweatshirt
How to Unlock: On Happiness Island at the entrance to the Statue of Happiness (Liberty) it’s sitting on the ground, walk over it and it’s yours.