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