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