I've used a strawberry babycord and a flowery cotton purchased at ebay for this. The buttons are vintage, I actually bought them at a tiny second hand store somewhere in Finnmark.(far north in Norway)
They wanted 1 NOK (about 20 cents) for each button.. I bought the 3 jars they had, ending up with thousands of old buttons! Got them a little cheaper ;)
The pattern is from Ottobre, they make really simple patterns even I can manage. I'm afraid Elina will be "that weird kid" who's always wearing something homemade. Or maybe it isn't weird anymore, but cool?