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