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