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