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