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