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