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