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