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