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