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