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