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