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