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