Instructions on how to make this princess dress light up using a Lily Pad and Arduino. Here is the link on Amazon to purchase the dress:

http://www.amazon.com/gp/product/B0018K0TR0/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1

Step 1: Video

Here is the video so you can listen to the music and see the lights flashing.

Princess Dress - Step #9
Download

Step 2: Things You Will Need.

You will need the dress, Lily Pad, four of the lights that come with it and conductive ribbon and thread.

Step 3: Getting Started

The first thing to do is sketch your project. It will make things easier later. Here I've drawn out the dress and where I want the lights to be. I put them on the ends of the petals, as you can see in picture 2 and 3.

Step 4: Placing the Lily Pad

Conveniently, this dress has a pocket sewn right into it. I placed the Lily Pad in it and sewed around it.

Step 5: Coding

You will need to have the program Arduino to code this. Here is the code I used, but you can tweak it to get different results:

int redLed=9; //the numbers are the PINS
int greenLed=11;
int blueLed=10;

void setup()
{
pinMode(redLed,OUTPUT);
pinMode(greenLed,OUTPUT);
pinMode(blueLed,OUTPUT);

}

void loop()
{
digitalColor();
}

void digitalColor()
{
//This LED is backwards. Low=on, HIGH=off, 0=on, 255=off
digitalWrite(redLed,LOW);
digitalWrite(greenLed,LOW);
digitalWrite(blueLed,LOW);
delay(500);

digitalWrite(redLed,HIGH);
digitalWrite(greenLed,HIGH);
digitalWrite(blueLed,LOW);
delay(500);

}

Step 6: Sewing

My sewing job isn't perfect, but it was functional. It is hard to sew on the thin fabric of the dress, so do the best you can. The negative of the Lily Pad needs to connect to one of the ribbon patches that will be sewn on the side. The negatives of the lights also need to connect to the negative on the Lily Pad. The positive sides of the lights need to be sewn to the A2, or whatever hole you programmed it to be. The second patch needs to be sewn to A5 or whatever you programmed that to be. And remember, don't let them touch or they will cause a short!

Step 7: Sewing Along the Petals

I put the lights at the bottom of the petal, and then sewed the negative line down one side, and the positive side down the other, which worked out perfectly. Although, underneath the petals they had to cross, which is where the complicated part begins. As a temporary solution I just used tape to separate them, and make sure they didn't touch. However there are many better ways to do that. Like more fabric, etc.

Step 8: Sewing the Patches

For my patches I used conductive ribbon. I put them on the seam from the armpit to the waistband so that when the girl tries on the dress puts her hands on her hips it will light up. Just sew it right down the middle or around it.