Apple recently shared a support document that gives instructions on how to make a face shield. The support document gives detailed instructions on how to make your face shield and also mentions that only experts should make it.
First, Apple gives the list of parts and required materials for manufacturing the shield. The parts include the shield, forehead band, and a strap. Apple suggests using Clear PET or PETG with 0.5 mm thickness for the shield and the forehead band. The strap Latex-free Silicone is to be used for the strap. Apple also mentions alternate materials if these are not available.

Apple also shares the fabrication methods to manufacture the shield. These methods include the laser cutting method, water jetting and the die-cutting method. Also, Apple mentions the advantage of each method in the notes.
Then Apple gives a detailed method for fabrication, how to cut the materials. The process includes the details on how to test and assemble the parts, how to pack etc.
Apple also provides design files at the page’s bottom. These files include all the instructions for completing the project, these files also include the specific manufacturing files and the 2D cut files and more. It anyone needs further help in understanding the process, they can contact Apple through the email provided in the support document.