Here’s a great idea from the mind of xkcd, a hierarchical map of Tic-Tac-Toe moves.  With differing maps for X and O, simply pick the map that corresponds to your side and follow the directions.  It takes a minute to get the hang of it, but it’s a great layout for a timeless classic.  The maps are made assuming X goes first.  Simply put your symbol in the largest red position of the position corresponding to where your opponent put their mark.  For example, X starts with the upper left, while O needs to first find the section of the board where X put their mark and follow the map correspondingly.