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)(11,14)(12,16)(13,15)(18,22)(23,31)(24,25)(26,32) involution — undirected(2,5)(6,8)(9,11,13,12)(10,14,15,16)(17,18,20,22)(19,26,27,32)(21,24,29,25)(23,30,31,28)(10,15)(14,16)(17,19,20,27)(18,23,22,31)(21,30,29,28)(24,26,25,32)(9,12,13,11)(10,16,15,14)(18,24)(21,29)(22,25)(23,26)(28,30)(31,32)(1,3,4,7)(2,6,5,8)(18,22)(23,31)(24,25)(26,32)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.