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