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