The knowledge for crafting an object can be bestowed on the player after offering food or gold nuggets at the knowledge altars at the Mystical Monuments.
You find the the bestowed knowledge in your knowledge docket. This docket has a capacity for 12 different "blueprints". There are more possible object to create than capacity in the docket. Therfore it is useful to forget a "blueprint". The knowlege can be saved on a sheet of paper and relearned later when needed.
Selecting one "blueprint" in your knowledge docket will give you the components list to the right. The components list will give you a view of the needed items. While crafting, all the required components need to be in the inventory and will be used up in the crafting process. A crafted item will appear in the inventory, crafted camp upgrades will be placed in the homecamp (and can only be crafted there) while crafted clothing will be put on the character immediately.