One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10)(11,14)(12,13)(15,16) involution — undirected(2,5)(6,8)(17,18,20,24,32,39,45,43,22,26,34,41,21,25,33,40)(19,27,28,42,35,48,47,37,30,44,46,36,29,38,31,23)(1,3)(2,6)(4,7)(5,8)(10,13)(14,16)(17,19,22,30)(18,23,26,37)(20,31,34,47)(21,35,32,29)(24,38,41,48)(25,42,39,36)(27,43,44,40)(28,45,46,33)(3,7)(6,8)(9,11,12,15)(10,14,13,16)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.