I personally like the gaiter-style mask. At least for me, it fogs my glasses less–and it’s easy to pull up or down if you’re active outside as your ability to socially distance fluctuates.
Unfortunately, I haven’t been able to find gaiters for sale specifically optimized to be great COVID-19 masks.
I’ve had a success putting together a gaiter that as best I can tell complies with the latest mask practices for fabrics and layers. (Note: please form your own conclusions–I’m just channeling what I’ve read online.)
Here’s how to make it. All no-sew, but you’ll need an iron and some materials linked in the instructions.
I started with a run-of-the mill neck gaiter that happened to be white polyester. You’ll want to find one with a nice snug fit over your nose.
I used fusible fabric bonding tape and an iron (like Stitch Witch) to make a 3-layer sheet: quilting cotton x 2 plus silk.
Then I used the fabric bonding tape again to attach it over the front of the interior of the gaiter. (This is important: do it on the inside, and do this step first. Read on for “why.”)
At the time I created “gaiter one-oh” that was about what I’d read was best practice. Since then I’ve read that polypropylene works well as a mask material. (Apparently it is an extruded rather than woven fabric, which helps with particle interdiction.)
“Oly-fun” is a brand name poly fabric. Unfortunately it has a low melting point. It’s also not as pleasant on your skin as cotton or silk.
So you’ll want to put it on the outside of the gaither, and do the ironing-on of the inside layer first.
I cut a piece sized to cover the front of the gaiter, and used fabric glue to attach it all around.
For both layers, attach them just shy of the upper elastic edge–that is to say, leave that line of elastic alone to do its grippy thing.
It’s worked great: I’ve done an hour-long workout without needing to adjust it once. The added layers haven’t compromised the fit.
The one limitation I’d note at this point is that hand-washing cold and hang-drying seems to be about the limit of what it can take if you want it to last.