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