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