I prefer masks that can take a replaceable PM2.5 filters, and has a nose bridge strip. I've been adding a second nose bridge strip to cut down on eyeglass fogging, and gluing the exhalation valves shut to cut any potential outgoing virus transmission (probably overkill, but better safe than sorry). They're not medical grade, but they're a whole lot better then two layers of cotton/spandex blend used for neck gaiters. Ironically, the disposable medical masks are easier to breathe through.

I also use diluted dish soap as a lens wash to cut down on fogging.