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