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