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