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