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