My first attempts at paper circuits were not too successful. I had trouble completing the circuit and my LEDs would not stay lit consistently. Now I've found a video that offers a tip that made all the difference. It is the Simple Circuit Demo video at http://www.nexmap.org/hacking-the-storybook. The tip was to fold the copper foil tape at a 90° angle and then fold it back over itself and also to do this where the battery connection occurs. I also plan to purchase circuit stickers since they are much larger and easier to work with than the tiny surface mount LEDs I had bought before.
Here are the results of my most recent effort to add a paper circuit to my handmade journal. I plan to have my third grade IDEA Lab students do this soon to enhance their journals.