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