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