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