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