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