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