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