Special thanks to cornfield, info take from Nodiatis forum.
Crafting consists of several phases.
1. You must actually be in possession of the item you wish to craft.
2. You must then dissassemble it. This will yield a Master Copy, and some resin, or dust if the item was an epic. You can trade for Master copies, and thus get them at a lower price than purchasing the item itself and dissassembling it. The master copy will require 3 items to move on to the next phase of crafting by making a consumable copy. This consists of some type of Sinew, a piece of Cloth, and a Dye, all of them item-level dependant.
3. Using a Quill Pen, you assemble one of each of the afore-mentioned items into a consumable copy. If you ask how it makes sense, you're using a sinew to write on a piece of cloth with a particular type of dye. This Consumable Copy then gives you instructions on how to actually craft the item itself. These consist af several types of items and various amounts of resins, or dust, in the case of an epic.
4. Gather the required items that are required for the item as listed in the Consumable Copy.
5. Depending on what Item you wish to craft, you can make the craftable item usually using the Forge in the Armory. In the case of fletching items, you will need to use the Fletchers Handbook instead. A Sewing Kit is neccessary for making Quivers.