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