Google Maps API, turn right/turn left

Hello,

I work on a project for my high school, which consists of making a flashing headset and to automate it thanks to Google Maps API, for example when you have to turn left the left LEDs flash.
I have already realized a program to display the steps of the desired route but I'm still looking for a way to flash the LEDs according to the route, do you have an idea?
Thank you for your answers !

atomike-toxic:
I have already realized a program to display the steps of the desired route but I'm still looking for a way to flash the LEDs according to the route, do you have an idea?

Please post the program of the first part, with description and circuit diagram (no Fritzing type spaghetti please, those images are mostly useless) of how those LEDs are connected.
As you already can display those steps (how?) that would be the obvious point to attach LED flashing code to.