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