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