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