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