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