In the age of Coronavirus the question often asked is - Do we or don't we...wear face masks?  As of now, the answer seems to be "yes, when out in public around others".

The follow up question is then, "but what do I do when my glasses fog up?"

Yahoo reports on the answer.
There are a few tricks to use to avoid this issue.  A study on surgeons found this is what they do to keep them from fogging up when a face mask is worn.

First, wash your spectacles with soapy water and shake off the excess, then let your glasses air dry

Second, you could f old down the top fourth of your mask if it fits loosely before wearing it. This makes the mask fit you more snugly and therefore your breath cannot escape out of the top and up onto your glasses.

Third, is to attach a folded tissue to the inside top of your mask, where it lies atop the bridge of your nose. This helps absorb the moisture from your breath, impeding condensation.

If possible stay home and mask free, but if you have to head out into the world, these tips should help