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