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