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