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