One vertex per element, one color per generator, with an edge from x to x·s.
(2,3)(5,6)(7,11)(8,12)(9,13)(10,14)(15,18)(16,19)(17,20)(21,22)(23,26)(24,27)(25,28)(29,34)(30,33)(31,35)(32,36) involution — undirected(1,2,4,3)(5,7,10,17)(6,11,14,20)(8,16,9,15)(12,19,13,18)(21,23)(22,26)(24,29)(25,30)(27,34)(28,33)(31,36)(32,35)(6,12)(7,15)(8,9)(13,14)(16,17)(18,19)(21,24)(22,27)(23,29)(25,31)(26,32)(28,35)(30,36)(33,34) involution — undirected(1,3,4,2)(24,31)(27,35)(29,36)(32,34)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.