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