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