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