At first I tried to figure out the system of the circuit and simplify it to be able to understand it. I extended the PCBs switch and LEDs to my own external paper electronics. This was harder than I thaught, and it took me a while to understand what the chip does and how exactly the wires have to be connected.
I was trying to come up with an idea to apply the chips functions to. The patterns in which the chip is programmed to make the lights blink reminded me of the flashy kids shoes I never had. So I just simplyfied and applied my paper-electronics to a smaller peace of cradboard as an add-on to a shoe. For the switch I used the orginal button, which I installed underneath the heel.