I'm taking a course this semester called Youth and Technology in Libraries, in which I was tasked with designing something using a Lilypad development board. In the following steps I will walk you through how I created my Christmas sweater with flashing lights and music.
Step 1: Materials
1. Protosnap Lilypad Development Simple Board
(NOTE: the board will come with a LiPo battery, several sewing needles, and two bobbins of conductive thread)
2. USB cable (you'll probably have a few of these laying around if you look - I used the cable for my Canon camera)
3. Christmas-themed sweater (I used this one)
4. Pair of tweezers to snap apart the board
Step 2: Uploading Your Code
For starters, you'll need to download the appropriate Arduino IDE for your operating system. You will also need to download the correct FTDI driver for your OS from this site. For my project I worked on Mac OS X Mavericks 10.9.2. If you're on a Mac and confused about the architecture of your processor, click on the Apple icon in the top left corner of your screen and choose "About this Mac." A screen should pop up that shows your processor. If your processor is anything other than an Intel Core Solo or Intel Core Duo, then you have a 64-bit processor.
Next, you want to copy and paste the code that I will attach here into the Arduino IDE. You will then connect your development board to your computer using the USB cable, and upload the code onto the board.
This code includes four different songs. For whichever song you want to play (I ultimately decided on "Deck the Halls"), change the tune number of that song to "(tune == 1)". "Jingle Bells" is the default.
NOTE: if the music playing drives you nuts while the board is connected to the USB (I know it did me!), then locate the loopSong variable and change it from "true" to "false". Then just change it back to true when you're finished.
Step 3: Sewing Your Board
Now that your code is uploaded to the development board, it's time to break off the components. For this step, I used a pair of tweezers to snap out each piece. Don't worry too much about applying pressure while doing this. You should definitely be careful, but I also found that the board was much less fragile than it looks.
Now you need to locate where on your sweater you would like to sew your various parts. I like symmetry, so I placed two of my LEDs at the top of the sweater and two at the bottom. The board and the speaker are hidden by being sewed inside the sweater. You need to design your layout before sewing so that your positive threads don't touch your negative threads.
Now, using the conductive thread included with the Lilypad kit, sew each pin on the board to its corresponding positive pin on each LED and the speaker. Once you've finished with that, you'll need to sew one negative thread that starts at the negative pin on the development board, and then connects to the negative pin on all four LEDs and the speaker.
NOTE: I'll include a diagram of my layout once I get the chance.