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