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