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