Solar Viewer for partial or total eclipses or sunspots
To make an effective and safe solar viewer for eclipses and sunspots, get a shoe box or larger and cut two 1" holes in one end and tape a white piece of paper to the inside wall opposite the holes.
Cover one of the holes with a piece of tin foil with a tiny round hole made with only the point of the smallest needle you can find and tape it with masking tape on all the edges.
The sharpest images are possible with a carefully-made, very small round hole with no burrs or tears.
Tape the box closed so there are no light leaks.
To use the Solar Viewer look through the peep-hole at a projection of the sun's image on the white piece of paper. Locate the peep-hole that you look through near enough to one edge of the box so you can put your eye very close to the hole. You want to block light to make the inside dark enough to see the dim image of the sun.
Aim the box so the light from the sun shows through the pinhole while you look through the other hole. You might have to use your hand to block some light to get a better view.
Try to make one and experiment long enough before the eclipse so you'll be ready when the time comes to enjoy it.