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