Masks can be made from cotton fabric and still be quite (~70% effective) (https://www.researchgate.net/publication/258525804_Testing_the_Efficacy_of_Homemade_Ma

Masks can be made from cotton fabric and still be quite (~70% effective) (https://www.researchgate.net/publication/258525804_Testing_the_Efficacy_of_Homemade_Masks_Would_They_Protect_in_an_Influenza_Pandemic https://www.researchgate.net/publication/258525804_Testing_t...). You can improvise a mask from paper towel and tissues that is ~90% effective (https://www.bkreader.com/2020/03/07/heres-a-diy-way-to-make-your-own-protective-face-mask/ https://www.bkreader.com/2020/03/07/heres-a-diy-way-to-make-...)