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