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