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