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