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