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