So, you want ensure you always win whenever you play the wonderful time-waster that is Squares? The secrets, believe it or not, is not to get greedy.
In this video, famed mathematician and game theorist Elwyn Berlekamp explains how you can win every hand of the game you play. A crucial first step: not taking every square you can. With patience, young grasshopper, comes the greater victory. [Numberphile]