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