Armor is especially important in FFXI, because of the great diversity in the armor itself. Unlike the previous Final Fantasy games, there are many different categories of armor, which all can be equipped to protect different regions of your character’s body. Armor can be purchased at any armor shop in one of the four main towns (San D’Oria, Bastok, Windurst, or Jeuno) or you can purchase it from the Auction House. It is recommended that all of your characters armor is purchased at the Auction House, because it is much cheaper to buy. You can also find some armor on other fiends after you kill them, or even get some during quests.
To equip a piece of armor, enter you menu, then go to “Equip”. You will then see a number of boxes, each box representing a different place to put armor. Click on the box representing the place you want to equip armor to, and you be asked to select an item in your inventory that will fit in the spot. Click the armor you want to use, and then it will be equipped. To remove armor, simply do the same, except click the item you already have equipped, and it will unequip that item.