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