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