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