There are many, many non-medical face mask tutorials and patterns available on Youtube and other websites. Most are based on scientific principles on how to reduce the spread of the coronavirus, and some are recommended by various doctors, nurses, and medical facilities, but these are all considered non-medical masks. There efficacy depends, in part, upon the materials used, the snugness of the fit, and precautions taken by the user. Here are a few links to face mask patterns, in alphabetical order, that we have found helpful.
CDC Guidance on Masks
Importance Information Regarding Your Cloth Face Coverings
41 Printable Olson and Pleated Face Mask Patterns by Hospitals
By a Nurse for a Nurse
Deaconess Hospital Face Mask
Fabricpatch.net collection of mask videos by a nurse/quilter.
Leah Day. This one has a pocket for a filter (furnace/AC filters, vacuum
cleaner bags, flannel, nonwoven interfacing, flannel, even paper
towels are suggested)
The Olson Mask
A Surgeon’s guide to making a face mask
How to Cut a Tee-Shirt into One Continuous Strip–for Face Mask Ties