Pictures have instructions, but basically what you need to do is cut pieces as shown, size of oven is variable, of course, but this scale model has a cooking chamber of 4x4x4inches. A box of 6x6x6 is the outer shell, and the space in between is filled with insulating material, i.e., cardboard, newspaper, or other insulating materials.
I ended up with square reflectors, with the mirrors (4 inch mirror tiles) glued on with spray adhesive. The reflectors are held in place by a piece of light cardboard glued onto the backs, and then this piece is inserted down into spaces between sheets of insulating cardboard.
The reflectors are a very passive system, and need only be adjusted a very little. In order to do that, I added the wood pieces as shown, held in place with a heavy rubber band. When adjusting mirrors, you learn how to look at the shadows of the boxes, and the actual reflected sunlight into the cooking chamber. Trial and error stuff.
Learning the timing comes with just a little practice, and I found that an hour and a half was sufficient to cook the egg to a soft boiled egg state.
I consider the experiment a success, and this stove could be used as a one person meal preparation unit that is easily transportable, even back packed, and is environmentally sound, a true "green" project.
To watch video, use this link: