One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6)(7,10)(8,9)(11,12)(13,14)(15,17)(16,18)(19,20)(21,22,25,28)(23,31,34,35)(24,29,26,30)(27,33,36,32)(2,4)(13,15,16,19)(14,17,18,20)(21,23)(22,27)(24,33)(25,34)(26,32)(28,36)(29,31)(30,35)(6,9)(10,12)(22,28)(23,32)(24,26)(27,35)(31,36)(33,34) involution — undirected(5,7,8,11)(6,10,9,12)(14,18)(17,20)(21,24,25,26)(22,29,28,30)(23,33,34,32)(27,31,36,35)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.