Get a lightproof box or container with a lid
Paint the inside black
Cut a small square opening on one side
Cover the opening with thin aluminum foil
Make a tiny pinhole in the center of the foil
Tape wax paper or tracing paper inside the opposite side as the screen
Seal all edges with black tape to block light leaks
Point the pinhole side at a bright scene
Remove the cover from the pinhole
View the image on the screen inside the camera
Adjust the distance between the pinhole and screen if needed
Keep the camera steady while taking the picture
Cover the pinhole again to stop the exposure
Develop or photograph the projected image if desired