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