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