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