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