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