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)(23,29)(24,31)(26,32)(28,34)(30,35)(33,36)(6,9)(10,12)(13,14)(15,18)(16,17)(19,20)(21,22)(23,26)(24,28)(25,27)(29,32)(30,33)(31,34)(35,36) involution — undirected(5,7)(6,10)(8,11)(9,12)(14,17)(18,20)(21,23,24,29,25,30,31,35)(22,26,28,32,27,33,34,36)(7,11)(10,12)(13,15,16,19)(14,18,17,20)(22,27)(26,33)(28,34)(32,36)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.