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)(18,24)(25,32)(26,28)(27,31) involution — undirected(2,5)(6,8)(17,18,22,24)(19,28,20,26)(21,27,23,31)(25,30,32,29)(10,13)(14,16)(17,19,22,20)(18,25,24,32)(21,29,23,30)(26,31,28,27)(9,11,12,15)(10,14,13,16)(17,20,22,19)(18,26,24,28)(21,29,23,30)(25,31,32,27)(1,3,4,7)(2,6,5,8)(17,21,22,23)(18,27,24,31)(19,29,20,30)(25,26,32,28)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.