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