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