Motifs are pre-made design patches that can be used to create custom clothing items with custom designs.
They're usually unlocked by collecting Yellow Loot Bags and opening them, by increasing a Character's Friendship level, or by purchasing them from events. At this time, they cannot be purchased with Star Coins. The most reliable way to collect Motifs is to feed Critters their favorite foods.
Motifs can be applied to clothing and wearable items when in the customization menu. They can be applied as layers, with more than one Motif able to be added as a layered image. The order of the layers can be changed after placement by clicking and dragging (holding the A button and dragging up and down on the controller).
Motifs that have a paintbrush symbol beside the image can have the color of that motif image changed when added to a clothing and wearable item.