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