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