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