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