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)(18,25)(19,31)(20,22)(21,23)(26,40)(28,45)(29,30)(32,34)(33,46)(35,47)(37,38)(39,42)(41,44)(43,48) involution — undirected(2,6)(7,8)(9,11,12,15)(10,13,14,16)(17,18,23,29,24,30,21,25)(19,26,34,43,35,44,33,39)(20,36,22,28,38,27,37,45)(31,42,46,41,47,48,32,40)(1,3,5,4)(2,7,6,8)(17,19,20,32,21,33,37,47,24,35,38,46,23,34,22,31)(18,26,36,40,25,39,45,48,30,44,27,41,29,43,28,42)(1,4,5,3)(2,8,6,7)(10,14)(13,16)(17,20,21,37,24,38,23,22)(18,27,25,28,30,36,29,45)(19,32,33,47,35,46,34,31)(26,41,39,42,44,40,43,48)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.