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