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