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