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