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