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