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