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