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