I know I'm not going out very often where there will be other people, and I know that finding any factory-produced mask will be difficult, if not impossible (I have friends who work in hospitals, and they can't/shouldn't get them for home use now), and so I was considering making a mask from a virus-shield 3M furnace filter (of which we happen to have a spare). Unfortunately, the YouTube videos that show how to do that, all involve sewing something... which ain't gonna happen.
Then my friend, Ted Frank, posted a video on how to make a mask from a T-shirt.
I did it, and it takes less than 15 minutes. Here are the steps and the photos.
First, find a T-shirt you don't want to keep as a T-shirt. Unfortunately, I had given away most of my less interesting T-shirts, and I hope the students who gave me this one won't be upset that I've used it to make a mask. Think of the trade off: T-shirt sits unworn in a drawer or is used to maybe somewhat reduce the probability of spreading a contagious disease to or from me. (I know, it ain't an N95 or whatever, but at least it'll fit tight).
The chalk in the next photo is important. It not only half-sorta helped me cut straight, but drawing the cut lines before cutting helped me avoid some serious mistakes.
Here is the shirt with my chalk lines. Notice that I drew two bottom lines. I drew the higher one of the two because I didn't really want the word "Assume" to be on the mask but then I realized the underarms of the sleeves will help hold the pieces in the front and back together. Also I wanted a longer (top-to-bottom) mask.
And if I were making another one, I'd probably leave some of the tops of the arms as well.
Those next chalk lines show where to cut so there will be two sets of ties on each side of the mask.
Now it's time to cut (you can probably do all this in less time than it takes to read what I did).
And here is the final result. Just tie it on and adjust it.
Before I go out, I'll probably put some tissue between the front and back. And to sterilize it after I've been out, I'll leave it in the sun on the balcony.