There are a multitude of fashion sets available in Forsaken World. Fashion sets are a separate set of equipment that lets your character stand out from the rest of the crowd.
You can get a free fashion set as soon as you enter Freedom Harbor for the first time by talking to the nearby Handmaiden NPC. This set is on a week-long timer though, so it isn't permanent.
To display a fashion set after you have equipped one, simply click the mask icon near your character's head in the character information screen. You can swap back and forth between your fashion set and regular combat set whenever you want. Fashion items become bound to you after equipping them.
While all fashion are paired with a particular set, try mixing and matching for a unique style!