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