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)(11,16)(12,14)(13,15)(19,26)(23,31)(27,29)(28,32) involution — undirected(1,3,4,8)(2,5,6,7)(17,18,22,24)(19,27,26,29)(20,21,30,25)(23,32,31,28)(9,11,13,12)(10,14,15,16)(17,19,20,28,22,26,30,32)(18,23,25,27,24,31,21,29)(2,6)(5,7)(17,20,22,30)(18,21,24,25)(19,28,26,32)(23,29,31,27)(3,8)(5,7)(9,12,13,11)(10,14,15,16)(17,21,20,18,22,25,30,24)(19,29,28,23,26,27,32,31)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.