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