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