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