|Attribute Points are awarded each time your Level increases. They can only be allocated while in Passive Mode and is done so by accessing Point Allotment within the Character Screen (Default Keybind on the PC: C). They are used to adjust Strength, Vitality, Dexterity, Intelligence, Mind, and Piety.
If you wish to reassign your points, the item The Keeper's Hymn, which you can buy from your Grand Company, lets you completely reset the points that you've allocated to your stats leveling your current class/job. You cannot reassign below your original base stats.