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