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