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)(11,13)(12,14)(15,16)(18,22)(19,26)(20,24)(23,28)(25,32)(29,30) involution — undirected(1,3,4,8)(2,5,6,7)(9,11)(10,13)(12,15)(14,16)(18,23)(19,26)(22,28)(27,31)(11,15)(13,16)(17,18,24,28,21,23,20,22)(19,25,31,32,26,30,27,29)(3,8)(5,7)(10,14)(11,15)(17,19,21,26)(18,25,23,30)(20,27,24,31)(22,29,28,32)(2,6)(5,7)(11,15)(13,16)(19,26)(25,30)(27,31)(29,32) involution — undirectedA 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.