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