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