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