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