If you are almost blind and drop your glasses and they break...
after you just survived a hurricane that wiped your town off the map.
(no images "yet"- Windows just BSOD'd again so I booted a Knoppix.)
Step 1: Supplies
I call these emergency "all-Rx SUNGLASSES" because they
use pinholes which have INFINITE focus but don't let much light in, including UV.
So you can really only use them during a sunny day.
A long piece of thin cardboard - at least 16 inches or 40 cm.
A magic marker
A bulletin board push-pin
Scissors (or anything that you can cut cardboard with.)
If you happen to have a pair of 3D glasses, use them as a stencil to
copy their shape and cut it out of the cardboard. Then you can skip the next step.
Step 2: Making the Frame
Cut out a strip of cardboard 1 or 2 inches wide and at least 16 inches long.
Bend it around your face and mark the middle which will be where your nose is
when the ends are hopefully covering your ears equally.
Cut out an arch that your nose can go through.
Bend creases on either side of your face.
Cut out arches that can rest on your ears.
Step 3: Making the Pinhole Lenses
Pick up the magic marker.
Put on the frame and look straight ahead.
Carefully mark the inside of the frame on the inside in front of your eyeballs while looking straight ahead in it.
(I assume the magic marker is soft and not likely to poke your eye out.)
Take the cardboard frame off your face and push the pin through the two marks.
Step 4: See What You Can See
Remove the pin and put the frames on and look around
to see if you can see anything. You should be trying to look
through the holes at a well-lit area. Move the frame around
if the holes don't line up.
If the holes are totally wrong, all I can say is try to figure out
where they should be, make new ones, try to close up the old ones.
Even with severe astigmatism you should be able to read signs with these that you can't without.
Look for a sign that says "OPTOMETRIST - OPEN". If you find one, get real glasses.