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