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