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