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