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