While some DIY-ers are making fancy, sewn versions, numerous sources are offering no-sew options. The Marine Corps Combat Service Support Schools, with headquarters in Camp Johnson, North Carolina, posted a tutorial to Facebook on how to fashion a cloth face mask out of the bottom of a T-shirt. You cut the tie strings right from the shirt, so no fussing with rubber bands or other elastic bits. And last week, Surgeon General Jerome Adams, M.D. appeared in a video on how to make one out of a cloth and rubber bands.

But that doesnt solve a big problem for eyeglass wearers: How to keep your glasses from fogging up when you have the mask on. When the warm vapor from your breath contacts the cooler surface of the lens, fog forms due to the surface tension between water molecules.

Heres what helps keep the fog away:

Use a Tissue

The Tokyo Metropolitan Police Department recommends folding up a facial tissue and placing it inside the top half of the mask. That creates some extra absorbency between your nose, which is creating the moisture, and your glasses, which are all too happy to show it. The Police Department diagram also suggests folding the top quarter of the mask inward for that extra layer.

Leave Some Soap on Your Glasses

A piece published in the journal Annals of The Royal College of Surgeons of England recommends taming the fog problem by washing your glasses with soapy water and shaking off the excessdont rinse them. Best to let them air dry, but the paper suggests you can also gently dry off the lenses with a soft tissue before putting them back on. The soap leaves a film behind that reduces the surface tension of the molecules. Swimmers do this all the timethey use a little bit of baby shampoo inside the goggles to prevent fogging there. Youll probably want to do some experimenting to see how much of which type of soap works for you.

If youre tempted to just wear your contacts, check out why experts say glasses might be your better bet right now.