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