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