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