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