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