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