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