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