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