One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(6,8)(9,10)(11,12)(13,16)(14,15) involution — undirected(5,6,7,8)(9,11)(10,14)(12,16)(13,15)(2,4)(9,12,13,14)(10,15,16,11)(1,2)(3,4)(9,11)(10,14)(12,16)(13,15) involution — undirected(9,11)(10,12)(13,15)(14,16) involution — undirected(9,10)(11,14)(12,15)(13,16) involution — undirectedA 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.