To make the butterfly wing pattern symmetrical, the LEDs are placed in identical, but mirrored, layouts. You can get display the same pattern in both halves by connecting the two strands to the same data line. In order to connect both halves of the Pebble stands to the power and data pins, you first need to combine their wires.

The power of one strip should be connected to the power of the other. The two grounds should also be connected, as should the two data-in lines.

This image shows how you'll connect them:

As shown in the Fritzing diagram above, you'll want to trim some wire back on each input side of the Pebble LED line and twist the same lines together such that you now have each like wire connected on the input sides of each strand. These three wires are then connected to the respective pads on the Mini Sparkle Motion: 5V, G/Ground and the Pebble Data in to pin 32.

You can solder straight onto the Mini Sparkle Motion, or add a screw terminal block connector (not included, sold separately) to the Mini Sparkle Motion and screw in the wires to make it easy to attach or detach the controller.

There are troubleshooting steps on Erin's page if later in the build the lights are not acting as intended.

The build above shows three colored wires connected to each Pebble LED strand end and then leading to the Mini Sparkle Motion, without a terminal block.