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