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)(21,22,24,27,25,28,31,34)(23,26,30,33,29,32,35,36)(5,7,9,15)(6,10,12,13)(8,14,16,20)(11,17,18,19)(2,4)(5,8,9,16)(6,11,12,18)(7,14,15,20)(10,17,13,19)(21,23)(22,26)(24,30)(25,29)(27,33)(28,32)(31,35)(34,36)(23,29)(26,32)(30,35)(33,36) 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.