You can be Attuned to 3 magic items at once. If a magic item has the Enchantment tag on it, you must be Attuned to it for you to use any of its abilities or gain any of its passive effects.
You can place Armor Enchantments on a suit of armor or clothing. The garment or armor does not have to be a complete suit of armor, but it must cover the majority of the torso. You can also use the Arcane Tattooist feat to tattoo an Armor Enchantment onto someone’s skin.
You cannot benefit from more than one item enhanced by Armor Enchantments at a time; if you attempt to Attune to a second one without de-Attuning to the first, the Attunement process fails.
You only gain the benefits of a magic suit of armor or clothing while wearing it and Attuned to it.
All of the enchantments listed in Accessory Enchantments, Armor Enchantments, and Weapon Enchantments require 9 Components of a Tier +1 higher than the item’s current Tier. Most mundane items are functionally Tier 0, and require a collection of Tier 1 components to Enchant them.
Once an Enchantment has been added to an item, its Tier is increased by +1, increasing the effects of any Enchantments on it and the Tier of the Components needed to apply a new Enchantment to it. For example, if you start with a Tier 0 unenchanted sword, and apply the Igniting Weapon Enchantment to it, you would need to consume 9x Tier 1 Components; after it is enchanted, the sword would be a Tier 1 weapon. Applying another Enchantment to it would require 9x Tier 2 Components, and would increase it to Tier 2; etc.
You must have at least the listed number of Required Aspects in the Components you use to craft a given Enchantment, whether a singular item or a Batch of ammunition. You cannot use any Components with the listed Prohibited Aspects. If an Enchantment lists a Granted Aspect, the item counts as a single Component with that Aspect for the purposes of further enchanting it. Granted Aspects stack with each other - for example, if you craft an Igniting and Erupting sword, it counts as 2 Fire Aspect components for the purpose of the next Enchantment you add to it.
If you have Components of the appropriate Materials (i.e. Metal, Wood, Textile, Leather, etc.) that also have the necessary Aspects, you can enchant an item in the process of crafting the item itself out of its base Components. This combined process is referred to as Forging an item, even when there is no metal involved in its creation.
If you are crafting a Batch of Ammunition enchanted with a Weapon Enchantment, it requires the same amount and Aspects of Components as a normal weapon, and enchants a Batch of 5 ammunition. This can be increased with the Fletcher, Experienced Scribe, and Efficient Crafting feats. You must still have enough raw material or pre-crafted base versions of any items you are enchanting for the increased Batch size, however — you don’t just create a new arrow out of nothing when you craft a Batch of magic arrows, for example.
Enchanted Items with the Material tag require a specific rare ingredient to craft the base item out of. You cannot add these Enchantments to an item after it has been created; they must be added during its creation.