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