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)(15,18)(16,17)(19,20)(21,22)(23,26)(24,28)(25,27)(29,33)(30,34)(31,36)(32,35) involution — undirected(6,9)(10,12)(21,23,29,30,25,32,24,31)(22,26,33,34,27,35,28,36)(1,2,3,4)(5,7)(6,10)(8,11)(9,12)(14,17)(18,20)(23,30)(24,29)(26,34)(28,33)(31,32)(35,36)(7,11)(10,12)(13,15,16,19)(14,18,17,20)(22,27)(26,35)(28,33)(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.