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