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