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