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