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