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