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