Thanks for your informative reply! I'll just imagine the board is a dance floor from the 70's and i'll do just fine!
But seriously, great illustration & explanation - starting by figure out which squares my king has to reach in order to win and where my opponents king has to be in order to prevent me from reaching those squares, and then work my way until i see the path from those squares to both kings. I will start by practicing this method on simpler positions to get the hang of it.
Btw, consider making a blog post about this. This information is rare and i am sure many would like to learn how to navigate difficult kings+pawns endgames using the method you described!
The reason Ka2 is the only winning move has to do with a2 being a corresponding square to h8, meaning that if the white king goes to a2, black king has to go to h8, otherwise he will not be able to defend. This information is given but i have no idea how figure that out on my own!
My question is how do you figure out which squares are related like that? Is there a method/technique for doing it?