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