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