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