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