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