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