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