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