One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(11,15)(14,16)(17,18)(19,23)(20,25)(21,26)(22,27)(24,28)(29,32)(30,31) involution — undirected(2,5)(6,8)(9,10)(11,14)(12,13)(15,16)(17,19,22,21)(18,23,27,26)(20,29,30,28)(24,25,32,31)(10,13)(14,16)(17,20)(18,24)(19,28)(21,29)(22,30)(23,31)(25,26)(27,32) involution — undirected(1,3,4,7)(2,6,5,8)(10,13)(14,16)(17,20)(18,25)(19,29)(21,28)(22,30)(23,32)(24,26)(27,31)(9,11,12,15)(10,14,13,16)(17,19,22,21)(18,26,27,23)(20,28,30,29)(24,25,32,31)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.