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