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