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