To equip an item, select a cat from the main Cat Select screen. Then choose one of the categories for head, body or paws. Swipe up or down to cycle through the cards that are available. If you have collected that card already, the ‘Equip’ button will be available. If not, the card will be greyed out.
Select an available card and tap ‘Equip’. This will send your cat back to the Item Select screen where you can choose another accessory to equip.
To unequip an item, tap the ‘Back’ button. This will remove any accessory from the cat.