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