A pinhole viewer is a simple device that allows you to safely view an image of the sun or other bright objects. It works by allowing light to pass through a small hole and project an image onto a surface behind it. Here are some common steps to make a pinhole viewer:

1. Find a cardboard box or tube and cover one end with a piece of aluminum foil.
2. Use a pin or needle to poke a small hole in the center of the aluminum foil.
3. Hold the pinhole viewer up to the sun and look through the other end to see the projected image of the sun on a surface behind it.
4. Adjust the distance between the pinhole viewer and the surface to focus the image.

Pinhole viewers can also be made using other materials, such as paper plates or index cards. They are a safe and easy way to view solar eclipses or other bright objects without damaging your eyes.