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