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