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