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