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