Since some sewing techniques are new to us, we learned them online (on the following website: https://learn.sparkfun.com/tutorials/lilypad-basics-e-sewing/sewing-with-conductive-thread). On our design, we used a circuit playground and three battery holders. For the circuit playground part, we need first to sew one hole (e.g., A3) with conductive tape. After that, sew one hole with the positive side of the LED (e.g., A5), sew the ground with the negative side of the LED. One circuit playground can hold at most 3 LEDs.