The possibilities…for starters:
My stash of 24…all washed and ironed!
Cowboy style? Perhaps with red or blue ones…not tie dye, pink camouflage, commercial or holiday.
I like the idea of having one around my neck and quickly pulling it up over nose and mouth. A triangle fold make for at least 2 layer coverage, if not 4 layers with another fold. Recommendations are to wash after each use.
My favorite application for bandanas is a drawstring bag. I made one in Girl Scouts kept it for years. That one was inspiration for birthday party favors in the 90s (before digital photography). Check out this post by
elfcroft 
Very pretty