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