Karen Dixon, Sue Chrysler, Beverly Kuhn, and Kay Fitzpatrick have put together some homemade mask resources. Thanks, TTI Quilters!

This is a link to a PDF from the Great Falls Clinic on how to make homemade masks:
https://tti-my.sharepoint.com/:b:/g/personal/d-sweeney_tti_tamu_edu/EblTou2RYFRHmpovNfqBq48B_oP520Wr-lJ0qs4phOujrw?e=VRjBeS

Additional instructions from Great Falls: https://www.gfclinic.com/approved-pattern-info-for-homemade-masks/

Other mask-making sites:

The Crafty Quilter site has a nice variety of options with good step-by-step photos. The list of tips way at the bottom is good.
https://thecraftyquilter.com/2020/03/versatile-face-mask-pattern-and-tutorial/

Craft Passion has a pattern that requires a pattern template. https://www.youtube.com/watch?v=KBR98YKAr7w

Sweet Red Poppy has a style with ties, rather than elastic. https://sweetredpoppy.com/how-to-sew-a-bias-tape-surgical-face-mask-with-flexible-nose/

Missouri Start Quilting also has video tutorials for styles with elastic and with ties.  https://www.missouriquiltco.com/msqc/tutorial/DIY-face-mask

The Centers for Disease Control has information on washing your mask. There are also instructions there for a gathered mask.
https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/diy-cloth-face-coverings.html