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