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