This page contains various hints concerning crafting in Prey. Crafting isn't overly complicated in this game, which is another reason to use it often. Learning its rules will let you constantly replenish the supply of the most important items.
For the purposes of crafting, you have to collect all junk you come across. It includes items such as wires, plates, fans, or plants that have no practical use. Try to make a habit of searching every newly visited loction and taking every interactive object from it.
Collecting useless stuff is going to fill up your inventory sooner or later (it can be expanded with certain human abilities). Before it happens, you should look around for a Recycler (like the one in picture 1). These devices let you convert junk into materials that can be then used to craft new items.
Place all junk in a Recycler (hold the indicated button in the inventory screen) and switch it on. Materials will come out from the right slot - picture 2 (they are divided into several types - organic, mineral, synthetic, and exotic).
Attention - "ready" materials can also be found in some locations. However, they are rare finds and you have to accept the fact that most of them have to be obtained with the use of Recyclers.
Attention - more valuable objects can be placed in Recyclers, as well. However, do it only when a given item is useless to you or if you came across a "duplicate" of the Wrench (you can preview what kind of materials you will receive by using a Recycler).
Obtaining plans, which are blueprints for items, is an important step in crafting in Prey. They are hidden in various places on Talos I and their locations are listed in the "Secrets and important items" chapter. Try to acquire new plans on a regular basis, especially the ones connected to the weapons you use (e.g. ammo for the Shotgun).
After you've acquired materials and plans, you can go to a Fabricator (like the one in the picture). The device is simple to use - you have to select a project from the list and place the required materials in the device (interact with a Fabricator and the game will automatically take the right materials from the inventory).