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