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