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