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