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