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