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