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