To unlock the achievement "Fashion-conscious" you must equip your character with a set of 6 class-specific items. The class-specific items refer to the base class of your character class. Note that accessoires such as necklaces, rings and talismans do not count towards this achievement; it is exclusively concerned with clothing and weapons.
For classes that utilize clothing from one class and weapons from another, focus solely on the clothing, not the weapons.
You can achieve this with either normal or epic items. Items should originate from the same section in the scrapbook. However, since typical items do not start from the first page, you will need to carefully count their placement.
Example Sets for a Mage Classes