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)(25,26,31,28)(27,34,30,32)(29,33,38,36)(35,40,37,39)(1,2)(3,6)(4,5)(7,8)(10,12)(15,17)(16,20)(22,23)(25,26,31,28)(27,32,30,34)(29,36,38,33)(35,40,37,39)(2,5)(3,7)(10,12)(13,21)(15,17)(18,24)(25,27,31,30)(26,32,28,34)(29,35,38,37)(33,39,36,40)(3,7)(6,8)(9,11,14,19)(10,15,12,17)(13,18,21,24)(16,22,20,23)(25,28,31,26)(27,34,30,32)(29,36,38,33)(35,40,37,39)(1,3)(2,6)(4,7)(5,8)(9,12,14,10)(11,15,19,17)(13,20,21,16)(18,22,24,23)(25,29)(26,33)(27,35)(28,36)(30,37)(31,38)(32,39)(34,40)(1,2)(3,6)(4,5)(7,8)(9,13)(10,16)(11,18)(12,20)(14,21)(15,22)(17,23)(19,24)(25,30,31,27)(26,34,28,32)(29,37,38,35)(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.