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