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