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