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