Using a bandana as a mask?
Cotton balls shoved by the bridge of your nose, and tucking it under your shirt, both help seal it, so air actually filters through it instead of going around the edges.
@emsenn one advantage to masks/bandanas that I don't see mentioned often enough:
you can't touch the sensitive parts of your face as easily.
Originally a small latinx / chicanx community, now open to all poc! Open to anyone from the culture cousins