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