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