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