Cars have horns and blinking lights, police cars have blaring sirens and flashing orbs– how do we communicate on bikes? Hand gestures, and maybe the occasional reflective strip on the back of a jacket or bicycle seat? Not for long. This DIY turn signal bicycle jacket uses Lilypad arduino technology to hook up simple, highly visible lights and arrows on the back of any sports jacket to help you communicate your path and pattern to any approaching vehicle. Controlling the light with simple hand depressors that you can hook up yourself, check out these basic instructions and handy, affordable technology to build your own communicative device to stay safe on the road.