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