This is the one were I give you some advice. Say you want to make a projection-mapped pop-up book. Say you want to set out and make something like what I made for Tome of the Seashore, only better. What are the kinds of things you should know before starting? What's the information that will get you jump-started on developing this exciting but underexplored technology? There are a few things, all of which I've broken down into sections, starting with simple advice regarding components and materials, and ending with more specific advice like how to read page turns.Why isn't this an audio podcast? Simple. Because I've already edited episode 14 and sick of waiting to publish it. If you want to hear Timothy and I talk about the project one last time, go ahead skip to the postmortem in episode 14. Otherwise, here's how to make an interactive pop-up book, as much as I now know.Use a TeensyWhen you're considering putting electronic components into a book, everything needs to be small and flat. You can't use resistors because those are round and bulbous. You can't use a microcontroller with built-in headers because those don't sit flush with the rest of the board. And then when you finally put all of your flat components inside the book, you have to find some way of making sure they aren't pushing against anything or else it will start to interfere with the natural functionality of the book.You can actually save yourself a lot of trouble by skipping those problems and just using a Teensy. Because the digital ports on a Teensy all have built-in pull up resistors, you can actually set them to INPUT_PULLUP and save yourself the trouble of engineering a circuit with physical resistors. And, because they don't come with any headers, you can simply solder directly to the board.Or use conductive thread to connect to the Teensy. In fact, seriously consider using conductive thread for this entire project. Solder is kind of a pain. It's not very good at sticking to copper tape (which you'll want to use as much as possibly since it can lie flat) and it's never a joy to remove when you make a mistake. If you're like me and you think with your hands, the ability to easily undo or build on top of previous work is a must. Plus, it doesn't feel too good burning yourself with a soldering iron and it smells kind of funny. Try to use conductive thread instead. Use Copper TapeI love copper tape. It's flat, it's conductive, and it's relatively cheap if you buy it online. Also, copper is just a nice color to look at, which I think is an important factor when choosing materials. Even if nobody else is going to be looking at the guts of your project, you will – so pick something that inspires you to make something beautiful.That being said, there are a few challenges inherent to using copper tape instead of wire for a circuit, all of which come down to the challenges ofmaintaining contact and adhesion.Establish ContactSometimes you want two strips of copper to exist nearby but not form a complete circuit together. The solution to that is simple: don't let them touch. If they touch, there's a very strong chance they'll form a circuit. See? Simple.However, the opposite is not necessarily true. Two strips of copper that come into contact with each other might form a connection, but they also might not. Copper tape is a little finicky in that regard. The only way to guarantee they will form a complete circuit is if you add a little bit of pressure.If the two strips always need to be touching together you can use adhesives to maintain that pressure. Just make sure that you never put insulting adhesives between the two strips and check for continuity after you're done putting them together. Also, know that all adhesives add a slight amount of thickness that may be greater than the thickness of the copper tape. This is where the importance of testing really comes in. Always test on a small sample before applying to the larger project and do whatever you